Photoelectric device and preparation method thereof, power utilization device and power generation device

Abstract

The invention relates to a photoelectric device and a preparation method thereof, a power utilization device and a power generation device. The photoelectric device comprises a perovskite layer; the perovskite layer comprises perovskite crystal grains, and metal iodide is distributed on the outer surfaces of at least one part of the perovskite crystal grains; in a GIWAXS two-dimensional diffraction pattern of the perovskite layer, the orientation included angle between the dominant crystal face of the metal iodide and the dominant crystal face of the perovskite crystal grain is smaller than or equal to 5 degrees. Wherein the GIWAXS refers to grazing incidence wide-angle X-ray scattering; the dominant crystal face is the crystal face corresponding to the strongest diffraction signal of the corresponding phase in a GIWAXS two-dimensional diffraction pattern. The photoelectric device has good device stability and good energy conversion efficiency.

Description

Technical Field

[0001] This application relates to the field of optoelectronic device technology, and further to optoelectronic devices and their preparation methods, electrical devices, and power generation devices. Background Technology

[0002] Optoelectronic devices are a class of devices that utilize photoelectric conversion mechanisms to perform photoelectric conversion. They can convert light energy into electrical energy for use in photovoltaics, or electrical energy into light energy for use in displays, lighting, and other fields. Accordingly, optoelectronic devices can be either photovoltaic devices or light-emitting devices. Taking photovoltaic devices as an example, as a highly efficient device that directly converts solar energy into electrical energy, they have been widely used in many fields. For instance, they are widely used on the rooftops of residential, commercial, and industrial buildings to form distributed photovoltaic power generation systems, or combined with energy storage devices for off-grid power systems, or integrated into portable electronic devices to provide power support for outdoor scenarios.

[0003] The core functional layer for photoelectric conversion in photovoltaic devices is the light-absorbing layer. Representative photovoltaic devices include crystalline silicon solar cells and perovskite solar cells. In perovskite solar cells, the light-absorbing layer is a perovskite layer containing perovskite material. Due to their high conversion efficiency and the ability to be fabricated using low-cost solution methods, perovskite solar cells have attracted widespread attention from the industry. Energy conversion efficiency is crucial for the practical application of perovskite solar cells. Therefore, improving the device stability and energy conversion efficiency of photovoltaic devices is of great significance. Summary of the Invention

[0004] According to various embodiments and examples of this application, this application provides an optoelectronic device, a method for fabricating the same, an electrical device, and a power generation device. This optoelectronic device exhibits good device stability and good energy conversion efficiency.

[0005] In some embodiments of the first aspect of this application, an optoelectronic device is provided, which includes a perovskite layer; the perovskite layer includes perovskite grains, and at least a portion of the outer surface of the perovskite grains is distributed with metal iodides;

[0006] In the GIWAXS two-dimensional diffraction pattern of the perovskite layer, the orientation angle between the dominant crystal plane of the metal iodide and the dominant crystal plane of the perovskite grain is less than or equal to 5°; where GIWAXS refers to grazing wide-angle X-ray scattering; the dominant crystal plane refers to the crystal plane corresponding to the strongest diffraction signal of the corresponding phase in the GIWAXS two-dimensional diffraction pattern.

[0007] In optoelectronic devices with a perovskite layer, by depositing a specially oriented metal iodide on the outer surface of at least a portion of the perovskite grains, the orientation angle between the dominant crystal plane of the metal iodide and the dominant crystal plane of the perovskite grain is made small (e.g., ≤5°). This allows for more effective contact between the metal iodide and the perovskite grain, thereby effectively passivating surface defects in the perovskite grains. Specifically, iodide ions in the metal iodide can passivate anionic vacancy defects on the surface of the perovskite grains, and metal ions in the metal iodide can passivate cation vacancy defects on the surface of the perovskite grains. This effectively suppresses the phenomenon of reduced degradation energy barrier of perovskite material caused by charged defect sites. In addition, the metal iodide can eliminate dangling bonds on the surface of the perovskite grains and achieve a field-effect passivation effect, forming type I / O on the surface of the perovskite grains. The band structure of I forms a grain boundary electric field, which prevents the movement of charged substances such as electrons and ions across grains, reducing or avoiding adverse phenomena such as carrier recombination and halogen phase separation. This can at least improve the energy conversion efficiency of optoelectronic devices; furthermore, reducing adverse phenomena such as halogen phase separation can further improve device stability. It is understood that we do not wish to be limited to the aforementioned theories.

[0008] In some embodiments of this application, in the GIWAXS two-dimensional diffraction pattern of the perovskite layer, the orientation angle between the dominant crystal plane of the metal iodide and the dominant crystal plane of the perovskite grain is less than or equal to 3°. In this case, the angle between the dominant crystal plane of the metal iodide and the dominant crystal plane of the perovskite grain is very small, and their orientations are essentially consistent, which is beneficial for further improving the effective contact between the metal iodide and the perovskite grain, thereby better improving the device stability and energy conversion efficiency.

[0009] In some embodiments of this application, the dominant crystal plane of the metal iodide is the same as the dominant crystal plane of the perovskite grain. In this case, it is beneficial for the metal iodide to contact the perovskite grain more effectively, which helps to reduce the mismatch stress at the contact point. This helps to reduce the density of interface defects, thereby reducing non-radiative recombination losses and thus providing a more stable and longer-lasting effective passivation effect.

[0010] In some embodiments of this application, the dominant crystal plane of the metal iodide and the dominant crystal plane of the perovskite grain are either (100) crystal plane or (111) crystal plane.

[0011] Both the (100) and (111) crystal planes can be used as the preferred crystal planes for metal iodides and perovskite grains.

[0012] The perovskite layer with the (100) crystal plane as the dominant orientation has a longer photogenerated carrier lifetime and better charge transport capability. The vertically oriented (100) crystal plane can optimize the charge transport path and reduce recombination loss at the interface.

[0013] The (111) crystal plane is the close-packed plane in the cubic crystal structure of perovskite. The perovskite layer with the (111) crystal plane as the dominant orientation has a more compact arrangement of surface atoms, a larger lattice spacing, and a limited ion migration channel, which can effectively suppress phase separation in the perovskite layer. In addition, the stronger the ability to block external stress intrusion such as water vapor, the better it can combine energy conversion efficiency and device stability.

[0014] In some embodiments of this application, when the dominant crystal plane of the perovskite grain is the (100) crystal plane, the average thickness of the (100) crystal plane of the perovskite grain in the normal direction is D. (100) And 700Å≤D (100) ≤1000Å, can be selected as 750Å≤D (100) ≤950Å. By controlling the average thickness of the (100) crystal plane of the perovskite grains in the perovskite layer in the normal direction within the above range, the growth of perovskite grains in the (100) crystal plane direction is more complete, the corresponding perovskite grain crystallinity is higher, the defects are relatively fewer, and the lattice direction of the (100) crystal plane is more matched with the migration path of charge carriers (electrons / holes), which is conducive to the transport of charge carriers along the thickness direction, reduces the scattering and recombination of charge carriers during the transport process, thereby improving the carrier mobility, improving the energy conversion efficiency and device stability of optoelectronic devices.

[0015] In some embodiments of this application, when the dominant crystal plane of the perovskite grain is the (111) crystal plane, the average thickness of the (111) crystal plane of the perovskite grain in the normal direction is D. (111) And 600Å≤D (111) ≤1000Å, can be selected as 650Å≤D (111) ≤950Å. By controlling the average thickness of the (111) crystal plane of the perovskite grains in the perovskite layer in the normal direction within the above range, the growth of perovskite grains in the (111) crystal plane direction is more complete, the corresponding perovskite grain crystallinity is higher, the defects are relatively fewer, and the atomic arrangement of the (111) crystal plane is more compact, the lattice spacing is larger, and the ion migration channels are restricted, which can effectively suppress phase separation in the perovskite layer and improve the device stability of optoelectronic devices.

[0016] In some embodiments of this application, in the one-dimensional integral curve of the GIWAXS two-dimensional diffraction pattern of the perovskite layer, the ratio of the integral area of ​​the diffraction peaks of the dominant crystal plane of the metal iodide to that of the dominant crystal plane of the perovskite grain is 0.5% to 5.5%, optionally 0.5% to 5%. In this case, the metal iodide is controlled at a low amount, which not only improves the device stability and energy conversion efficiency through effective passivation, but also significantly suppresses the photocatalytic effect of the metal iodide on the perovskite grain, thereby significantly reducing the risk of accelerated degradation of the perovskite grain caused by metal iodide under external stress conditions such as light irradiation, which is beneficial for achieving better long-term device stability.

[0017] In some embodiments of this application, at least a portion of the metal iodide has a thickness of 20 Å to 50 Å on the outer surface of the perovskite grains. In this case, the metal iodide on the outer surface of the perovskite grains is controlled to a relatively thin thickness, which is more conducive to effectively suppressing the photocatalytic effect of the metal iodide on the perovskite grains while simultaneously exerting a passivation effect, and is more conducive to achieving a long-term, stable, and effective passivation effect of the metal iodide.

[0018] In some embodiments of this application, at least a portion of the metal iodide is located at the grain boundaries of the perovskite grains. This allows for effective connection between the perovskite grains at the grain boundaries, increasing the contact area between the metal iodide and the perovskite grains, thereby providing better passivation and further improving the energy conversion efficiency of the device.

[0019] In some embodiments of this application, the perovskite layer has a first surface and a second surface that are opposite to each other in the thickness direction of the perovskite layer; wherein at least a portion of the metal iodide is located on at least one of the first surface and the second surface. In this case, the metal iodide can play a role in chemical passivation and physical passivation at the first surface and / or the second surface, thereby improving the device stability and energy conversion efficiency of the optoelectronic device.

[0020] In some embodiments of this application, the perovskite layer has a first surface and a second surface that are opposite to each other in the thickness direction of the perovskite layer; the distribution content of the metal iodide at the grain boundaries of the perovskite grains is higher than the sum of the distribution contents on the first surface and the second surface of the perovskite layer. In this case, the distribution content of the metal iodide at the grain boundaries is higher than the distribution content on both sides (the first surface and the second surface) of the perovskite layer. That is, the metal iodide is more distributed in the perovskite bulk phase, while the distribution content on the two sides of the perovskite layer is relatively less. This not only provides a long-term, stable, and effective passivation effect, but also helps to reduce the potential adverse effects of the metal iodide distributed on the two sides of the perovskite layer in the thickness direction on charge transport, thus improving energy conversion efficiency.

[0021] In some embodiments of this application, the perovskite grains on the outer surface where the metal iodide is distributed are referred to as the first perovskite grains; the proportion of the first perovskite grains to the total number of perovskite grains in the perovskite layer is 60% to 100%, and can be selected as 90% to 100%.

[0022] By controlling the proportion of the first perovskite grain relative to the total number of perovskite grains in the perovskite layer to be relatively high, more perovskite grains can be passivated by metal iodides, which is beneficial to further improve the device stability and energy conversion efficiency of optoelectronic devices.

[0023] In some embodiments of this application, the average size of the perovskite grains in the perovskite layer is 0.5 μm to 3 μm.

[0024] By controlling the average size of perovskite grains in the perovskite layer to be within the aforementioned relatively large range, it is beneficial to reduce the number of grain boundaries and achieve better energy conversion efficiency and device stability.

[0025] In some embodiments of this application, the metal element in the metal iodide includes one or more of lead, tin, and chromium.

[0026] In some embodiments, the metal element in the metal iodide includes lead.

[0027] By controlling one or more of the metal elements in the metal iodide, including lead, tin, and chromium, the ion size and valence state of these three metal elements are suitable for occupying B-site defects in the perovskite lattice. Among them, Pb also has advantages such as stable valence state and universal applicability to various band gaps; Cr and Sn ions are smaller than Pb ions, allowing for selective release of grain boundary stress caused by composition and processing, thus stabilizing grain boundaries in a third aspect—mechanical stress—in addition to chemical and physical passivation. Furthermore, Cr cations are more stable than Sn cations. 2+ It is more stable and less prone to changes in price state that could introduce additional defects.

[0028] In some embodiments of this application, the perovskite layer includes a first perovskite material, which includes iodine and iodine elements.

[0029] When the perovskite material in the perovskite layer includes lead and iodine, the Pb provided by the metal iodide... 2+ and I -It exhibits better passivation effects with lead and iodine vacancies in the perovskite layer. Furthermore, the energy level interaction between iodine and lead elements can form a suitable band gap, and the common defects in this lattice structure are all shallow energy level defects, which have a relatively small impact on the final device efficiency, thus facilitating the formation of high-efficiency devices.

[0030] In some embodiments of this application, the first perovskite material includes at least two of iodine, bromine, and chlorine.

[0031] Chloride ions promote high-quality crystallization of perovskite during the crystallization process, reducing defect density. Bromine facilitates the formation of a more stable perovskite mesophase during crystallization, resulting in perovskite with higher crystallinity. Furthermore, the addition of bromine can significantly widen the band gap of perovskite, thus benefiting its application in multilayer modules.

[0032] The anions of perovskite materials include at least two of the aforementioned halogen anions, which can combine low defect concentration and high-quality crystallization, while giving full play to the comprehensive advantages of perovskite solar cells, such as adjustable bandgap and applicability to single-junction and tandem technologies.

[0033] In some embodiments of this application, the perovskite layer contains a modifier, the modifier comprising diC 2-6 Alkylamine hydrochloride and diC 2-6 One or more of alkylamine thiocyanates;

[0034] In some embodiments, the modifier includes one or more of dipropylamine hydrochloride, dibutylamine hydrochloride, diethylamine thiocyanate, dipropylamine thiocyanate, and dibutylamine thiocyanate.

[0035] The aforementioned modulators can play a role in regulating and promoting the formation of metal iodides with advantageous orientation during the formation of perovskite layers. In the prepared optoelectronic devices, these modulators may remain at the grain boundaries, which can play a certain passivation role, passivating both cation vacancy defects and anion vacancy defects.

[0036] In some embodiments of this application, the area of ​​the perovskite layer is greater than or equal to 0.09 cm² in a direction perpendicular to the thickness of the perovskite layer. 2 .

[0037] By setting metal iodides with a small preferred orientation angle on the surface of perovskite grains through the aforementioned embodiments, grain boundary passivation can be uniformly and effectively carried out over a large area when the perovskite layer area is large. This provides a stable and long-term effective passivation effect, which is beneficial to improving the energy conversion efficiency and device stability of large-area devices.

[0038] In some embodiments of this application, the optoelectronic device includes a photovoltaic device or a light-emitting device. The aforementioned perovskite layer can be used in photovoltaic devices or light-emitting devices to help improve the energy conversion efficiency and device stability of photovoltaic devices or light-emitting devices.

[0039] In some embodiments of this application, the optoelectronic device is a photovoltaic device, which includes a solar cell; the solar cell includes the perovskite layer.

[0040] The aforementioned perovskite layer can be incorporated into solar cells to improve the photoelectric conversion efficiency and device stability of solar cells.

[0041] In some embodiments of this application, the optoelectronic device includes a solar cell, which is a multi-junction solar cell, and the multi-junction solar cell includes a first cell unit, which includes the perovskite layer.

[0042] The aforementioned perovskite layer can be incorporated into multi-junction solar cells to improve the photoelectric conversion efficiency and device stability of multi-junction solar cells.

[0043] In some embodiments of this application, the multi-junction solar cell further includes a second cell stacked with the first cell; the second cell and the first cell are connected by an interconnect layer, or the second cell and the first cell are isolated by an insulating layer; the second cell includes a light-absorbing layer, and the light-absorbing layer and the perovskite layer have different band gaps.

[0044] When solar cells are multi-junction solar cells, they are beneficial for improving the utilization rate of incident light, while also possessing the aforementioned advantages of high photoelectric conversion efficiency and high device stability. Multi-junction solar cells can be monolithic integrated tandem solar cells or mechanically tandem solar cells, offering flexibility in form and a wide range of applications.

[0045] In some embodiments of this application, the light-absorbing layer in the second battery cell includes a semiconductor active material, which includes one or more of the following: a second perovskite material, a silicon-containing semiconductor material, copper zinc tin sulfide, copper zinc tin selenide, copper zinc tin selenide sulfide, copper indium gallium selenide, copper indium gallium diselenide, copper indium selenide, cadmium telluride, gallium arsenide, and organic active materials.

[0046] The aforementioned embodiments can be universally applied to the aforementioned different types of multi-junction solar cells.

[0047] In some embodiments of this application, the multi-junction solar cell includes a first electrode, a perovskite layer, an interconnect layer, a light-absorbing layer, and a second electrode stacked together; wherein the interconnect layer is located between the perovskite layer and the light-absorbing layer; the first electrode is located on the side of the perovskite layer facing away from the interconnect layer, and the second electrode is located on the side of the light-absorbing layer facing away from the interconnect layer. Thus, two cell units in the multi-junction solar cell are connected through the interconnect layer to achieve current matching between the two cell units. This results in a relatively smaller size, the ability to absorb light of different wavelengths, a wider absorption spectrum range for the multi-junction solar cell, and an improved photoelectric conversion efficiency.

[0048] In some embodiments of this application, the multi-junction solar cell includes a first electrode, the perovskite layer, a third electrode, an insulating layer, a fourth electrode, a light-absorbing layer, and a second electrode stacked together. The third electrode, the insulating layer, and the fourth electrode are stacked between the perovskite layer and the light-absorbing layer. The third electrode is disposed on the side of the insulating layer facing the perovskite layer, the fourth electrode is disposed on the side of the insulating layer facing the light-absorbing layer, the first electrode is located on the side of the perovskite layer away from the third electrode, and the second electrode is located on the side of the light-absorbing layer away from the fourth electrode. Thus, the multi-junction solar cell forms a mechanically stacked cell. The insulating layer isolates the two cell units, preventing direct conduction of charge carriers and eliminating the need for current matching. Furthermore, each cell unit has its own separate positive and negative electrodes for current extraction, allowing for flexible circuit adjustments.

[0049] In some embodiments of this application, the optoelectronic device is a photovoltaic device; the optoelectronic device satisfies one or more of the following characteristics:

[0050] (a1) The perovskite layer is contained in the inverse or formal structure of the optoelectronic device;

[0051] (a2) The optoelectronic device includes a first charge transport layer and a second charge transport layer, wherein the perovskite layer is stacked between the first charge transport layer and the second charge transport layer; wherein, one of the first charge transport layer and the second charge transport layer is a hole transport layer and the other is an electron transport layer.

[0052] The aforementioned implementation methods can be universally applied to photovoltaic devices with formal or inverted structures, thereby improving photoelectric conversion efficiency and device stability.

[0053] Furthermore, the aforementioned advantages of the perovskite layer do not depend on the positional relationship between the hole transport layer and the electron transport layer stacked with the perovskite layer, and can be utilized in devices with different structures.

[0054] In some embodiments of the second aspect of this application, a method for fabricating an optoelectronic device is provided, comprising the following steps:

[0055] A perovskite precursor solution is prepared; wherein the perovskite precursor solution includes perovskite precursor raw materials and solvent, and the perovskite precursor solution also includes a metal iodide additive, the metal iodide additive having a dominant crystal face; optionally, the perovskite precursor solution also includes a regulator.

[0056] The perovskite precursor solution is coated, dried, and laser annealed to form a perovskite layer; wherein, the laser annealing includes annealing at a first temperature and a second temperature, wherein the first temperature is lower than the second temperature.

[0057] The formed perovskite layer comprises perovskite grains, and at least a portion of the outer surfaces of the perovskite grains are distributed with metal iodides; in the GIWAXS two-dimensional diffraction pattern of the perovskite layer, the orientation angle between the dominant crystal plane of the metal iodide and the dominant crystal plane of the perovskite grain is less than or equal to 5°; wherein, GIWAXS refers to grazing wide-angle X-ray scattering; the dominant crystal plane refers to the crystal plane corresponding to the strongest diffraction signal of the corresponding phase in the GIWAXS two-dimensional diffraction pattern.

[0058] After coating the perovskite precursor solution, some solvent can be removed by vacuum drying. This solvent removal process helps the perovskite precursor material form a perovskite mesophase film containing some residual solvent. During annealing, through the synergistic effect of laser annealing at the first and second temperatures, the metal iodide components in the perovskite mesophase film can be gradually, efficiently, precisely, and uniformly guided to the outer surface of the perovskite grains. In the laser gradient annealing process, the low-temperature annealing at the first temperature allows for appropriate decomposition of the mesophase, inducing the perovskite mesophase components to slowly pre-crystallize under relatively high residual solvent content, and utilizing the residual solvent to uniformly and slowly distribute the metal iodides to the perovskite grain boundaries. The high-temperature annealing at the second temperature, under the induction of the metal iodides with dominant orientation, allows the perovskite components to form high-quality crystals with highly consistent dominant orientation crystal faces, ultimately uniformly positioning the dominant orientation metal iodides on the outer surface of the perovskite grains. It is understood that this is not intended to be limited to the aforementioned theory.

[0059] Furthermore, in the presence of a regulator, the regulator can penetrate the interlayer of the layered structure of the perovskite precursor material (such as BX2), thereby expanding the interlayer spacing of the BX2 crystal structure. A larger interlayer spacing allows organic amine salts such as FA in the precursor solution to more easily enter the BX2 structure, thus enabling the perovskite to grow along the dominant orientation of BX2 during subsequent annealing steps, crystal growth, and fusion, thereby controlling the crystallization quality of the perovskite grains.

[0060] In some embodiments of this application, the method for fabricating the optoelectronic device satisfies one or more of the following features:

[0061] (b1) The vacuum drying is carried out at a temperature of 20°C to 30°C, a pressure of 80 Pa to 150 Pa, and a duration of 15 to 25 seconds.

[0062] Optionally, after the vacuum drying process, the mass percentage of the residual solvent is 10% to 20%, based on the initial solvent content before vacuum drying.

[0063] (b2) The regulator includes diC 2-6 Alkylamine hydrochloride and diC 2-6 One or more of alkylamine thiocyanates;

[0064] Optionally, the regulator includes one or more of dipropylamine hydrochloride, dibutylamine hydrochloride, diethylamine thiocyanate, dipropylamine thiocyanate, and dibutylamine thiocyanate;

[0065] The aforementioned types of regulators are beneficial for better exerting the aforementioned effects;

[0066] (b3) The molar percentage of the regulator relative to the perovskite precursor raw material is 0 to 3.5%, and can be selected as 0.45% to 3.5%;

[0067] At this point, it is advantageous to better control the dominant orientation of metal iodides during the perovskite crystallization process and the orientation angle of the dominant crystal planes of metal iodides on the outer surface of the perovskite grains, and it is also advantageous to achieve high crystallization quality at the same time.

[0068] (b4) The first temperature is 85℃~95℃, and the second temperature is 95℃~105℃;

[0069] Optionally, the laser annealing time at the first temperature is 1s to 5s, and the laser annealing time at the second temperature is 5s to 15s;

[0070] (b5) The laser power for laser annealing at the first temperature is 100W~200W, and the laser power for laser annealing at the second temperature is 550W~650W.

[0071] In some embodiments of the third aspect of this application, an electrical device is provided, which includes at least one of the optoelectronic devices described in the first aspect of this application and optoelectronic devices prepared by the preparation method of the optoelectronic devices described in the second aspect of this application.

[0072] In some embodiments of the fourth aspect of this application, a power generation device is provided, which includes at least one of the optoelectronic devices described in the first aspect of this application and optoelectronic devices prepared by the preparation method of the optoelectronic devices described in the second aspect of this application.

[0073] Both the power-consuming devices and power-generating devices containing the aforementioned optoelectronic devices can leverage the advantages of optoelectronic devices.

[0074] Details of one or more embodiments or examples of this application are set forth in the following drawings and description. Other features, objects, and advantages of this application will become apparent from the specification, drawings, and claims. Attached Figure Description

[0075] To better describe and illustrate the embodiments, examples, or models provided in this application, reference may be made to one or more accompanying drawings. Additional details or examples used to describe the drawings should not be considered as limiting the scope of any of the disclosed applications, the currently described embodiments, examples, or models, or the best mode of these applications as currently understood. Furthermore, the same reference numerals denote the same parts throughout the drawings. It should also be noted that the drawings are drawn in a simplified form and are only intended to facilitate and clarify the illustration of this application. The various dimensions of each part shown in the drawings are arbitrarily shown and may be precise or not drawn to scale. For example, the dimensions of parts are appropriately exaggerated in some places in the drawings to make the illustration clearer. Unless otherwise specified, the parts in the drawings are not drawn to scale. This application does not limit every dimension of every part. In the drawings:

[0076] Figure 1 This is a schematic diagram showing the distribution of metal iodides in the perovskite layer of an optoelectronic device according to an embodiment of this application; metal iodides are distributed on the outer surface of the first perovskite grain.

[0077] Figure 2 This is a schematic diagram showing the distribution of metal iodides in the perovskite layer of an optoelectronic device according to an embodiment of this application; metal iodides are distributed at the grain boundaries of the perovskite grains.

[0078] Figure 3This is a schematic diagram showing the distribution of metal iodides in the perovskite layer of an optoelectronic device according to an embodiment of this application; metal iodides are distributed at the grain boundaries of the perovskite grains.

[0079] Figure 4 This is a schematic diagram showing the distribution of metal iodides in the perovskite layer of an optoelectronic device according to an embodiment of this application; metal iodides are distributed on the first and second surfaces of the perovskite layer, and the first and second surfaces are opposite to each other in the thickness direction (i.e., the Z direction) of the perovskite layer.

[0080] Figure 5 This is a schematic diagram showing the distribution of metal iodides in the perovskite layer of an optoelectronic device according to an embodiment of this application; metal iodides are distributed at the grain boundaries of the perovskite grains and on the first and second surfaces of the perovskite layer.

[0081] Figure 6 This is a schematic diagram of the structure of an optoelectronic device according to an embodiment of the present application. The optoelectronic device includes a perovskite layer and at least one charge transport layer stacked together; the charge transport layer can be a hole transport layer or an electron transport layer.

[0082] Figure 7 This is a schematic diagram of the structure of an optoelectronic device according to an embodiment of the present application. The optoelectronic device includes a first charge transport layer, a perovskite layer and a second charge transport layer stacked together, wherein the first charge transport layer and the second charge transport layer are respectively disposed on both sides of the perovskite layer in the thickness direction of the perovskite layer.

[0083] Figure 8 This is a schematic diagram of the structure of an optoelectronic device according to an embodiment of the present application. The optoelectronic device includes a first electrode, a first charge transport layer, a perovskite layer, a second charge transport layer, and a second electrode stacked together. In the thickness direction of the perovskite layer, the first charge transport layer and the second charge transport layer are respectively disposed on both sides of the perovskite layer. The first electrode is disposed on the side of the first charge transport layer away from the perovskite layer, and the second electrode is disposed on the side of the second charge transport layer away from the perovskite layer.

[0084] Figure 9 This is a schematic diagram of the structure of an optoelectronic device according to an embodiment of the present application. The optoelectronic device includes a substrate layer, a first electrode, a first charge transport layer, a perovskite layer, a second charge transport layer, and a second electrode stacked together. In the thickness direction of the perovskite layer, the first charge transport layer and the second charge transport layer are respectively disposed on both sides of the perovskite layer. The first electrode is disposed on the side of the first charge transport layer away from the perovskite layer, the second electrode is disposed on the side of the second charge transport layer away from the perovskite layer, and the substrate layer is disposed on the side of the first electrode away from the perovskite layer.

[0085] Figure 10This is a schematic diagram of the structure of an inverted optoelectronic device according to an embodiment of this application. The optoelectronic device includes a substrate layer, an incident electrode, a hole transport layer, a perovskite layer, an electron transport layer, and a back electrode stacked together. In the thickness direction of the perovskite layer, the hole transport layer and the electron transport layer are respectively disposed on both sides of the perovskite layer. The incident electrode is disposed on the side of the hole transport layer away from the perovskite layer, the back electrode is disposed on the side of the electron transport layer away from the perovskite layer, and the substrate layer is disposed on the side of the incident electrode away from the perovskite layer.

[0086] Figure 11 This is a schematic diagram of the structure of an optoelectronic device according to an embodiment of this application. The optoelectronic device includes a substrate layer, an incident electrode, an electron transport layer, a perovskite layer, a hole transport layer, and a back electrode stacked together. In the thickness direction of the perovskite layer, the hole transport layer and the electron transport layer are respectively disposed on both sides of the perovskite layer. The incident electrode is disposed on the side of the electron transport layer away from the perovskite layer, the back electrode is disposed on the side of the hole transport layer away from the perovskite layer, and the substrate layer is disposed on the side of the incident electrode away from the perovskite layer.

[0087] Figure 12 This is a schematic diagram of the structure of an optoelectronic device according to an embodiment of the present application. The optoelectronic device is provided with a first channel region, a second channel region and a third channel region.

[0088] Figure 13 This is a GIWAXS two-dimensional diffraction pattern of the perovskite layer of the optoelectronic device in Embodiment 1 of this application.

[0089] Figure 14 This is a schematic diagram of an electrical device according to an embodiment of this application, in which an optoelectronic device is used as a power generation device.

[0090] Explanation of reference numerals in the attached figures:

[0091] 10, Optoelectronic device; 110, First perovskite grain; 210, Metal iodide; 211, First metal iodide (located at the grain boundary of the perovskite grain); 212, Second metal iodide (located at the first and / or second surface of the perovskite layer); Z, Thickness direction of the perovskite layer; 100, Perovskite layer; 101, First surface; 102, Second surface; 300, Charge transport layer; 310, First charge transport layer; 320, Second charge transport layer; 410, First electrode; 420, Second electrode; 500, Substrate layer; 610, Hole transport layer; 620, Electron transport layer; 700, Light-incident side electrode; 800, Back electrode; P1, First channel region; P2, Second channel region; P3, Third channel region; 6, Electrical device. Detailed Implementation

[0092] The following describes in detail, with appropriate reference to the accompanying drawings, some embodiments and examples of the optoelectronic device and its fabrication method, electrical device, and power generation device of this application. However, some unnecessary details may be omitted. For example, detailed descriptions of well-known matters and repetitive descriptions of practically identical structures may be omitted. This is to avoid unnecessarily lengthy descriptions and to facilitate understanding by those skilled in the art. Furthermore, the accompanying drawings and the following description are provided to enable those skilled in the art to fully understand this application and are not intended to limit the subject matter of the claims.

[0093] The "range" disclosed in this application can be defined in the form of a lower limit and an upper limit. A given range is defined by selecting a lower limit and an upper limit, which define the boundaries of a particular range. Ranges defined in this way can include or exclude endpoints. Any endpoint can be included or excluded independently and can be combined arbitrarily; that is, any lower limit can be combined with any upper limit to form a range. For example, if ranges of 60-120 and 80-110 are listed for a specific parameter, it is expected that ranges of 60-110 and 80-120 are also included. Furthermore, if minimum range values ​​1 and 2 are listed, and maximum range values ​​3, 4, and 5 are also listed, then the following ranges are all expected: 1-3, 1-4, 1-5, 2-3, 2-4, and 2-5. In this application, unless otherwise stated, the numerical range "ab" represents a shortened representation of any combination of real numbers between a and b, where a and b are real numbers. For example, the numerical range "0-5" indicates that all real numbers between "0" and "5" have been listed in this article; "0-5" is simply a shortened representation of these numerical combinations. Furthermore, when describing a parameter as an integer ≥ 2, it is equivalent to listing integers such as 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, and 12 for that parameter. For instance, when describing a parameter as an integer selected from "2-10", it is equivalent to listing the integers 2, 3, 4, 5, 6, 7, 8, 9, and 10.

[0094] In this application, the term "numerical value" includes the number itself and its reasonable approximations. The definition of "numerical value" can apply to discrete numerical points or to the endpoints of a numerical range. Unless otherwise specified, the term "approximation" covers a numerical interval based on a reasonable range of fluctuations of the number itself. This reasonable range of fluctuations can vary depending on the type and magnitude of the number. This reasonable range of fluctuations can be reasonably determined based on the accuracy of the testing or measurement method. Therefore, when referring to a numerical value or a numerical range, unless otherwise specified, it should be understood that the numerical value includes its reasonable approximation, and the numerical range includes reasonable approximations at both endpoints. Those skilled in the art will understand that acceptable fluctuation ranges of the relevant approximations can be included within the definition of the numerical value or the numerical range. In this application, unless otherwise specified, "N1" can be reasonably understood as "about N1," and "N1~N2" can be reasonably understood as "about N1 to about N2," where N1 and N2 are two unequal numerical values.

[0095] In this application, unless otherwise specified, "about" means within a reasonable range above and below the number, and the range of fluctuation may vary depending on the type and value of the number. For example, a range of ±10%, ±5%, ±2%, ±1% may be allowed.

[0096] In this application, the terms "multiple," "various," or "multiple items" are used unless otherwise specified, referring to a quantity greater than or equal to 2. For example, "one or more" means one item or two or more (greater than or equal to) items. It can be understood that when "any number of" items are involved, it refers to any suitable combination of multiple items, that is, a combination of "any number of" items in a manner that does not conflict and enables the implementation of this application.

[0097] Unless otherwise specified, all embodiments and optional embodiments of this application can be combined to form new technical solutions.

[0098] In this document, the term "embodiment" means that a particular feature, structure, or characteristic described in connection with an embodiment may be included in at least one embodiment or implementation of this application. The appearance of this phrase in various places throughout the specification does not necessarily refer to the same embodiment, nor is it a separate or alternative embodiment mutually exclusive with other embodiments. It will be explicitly and implicitly understood by those skilled in the art that the embodiments described herein can be combined with other embodiments. The term "implementation" as used herein has a similar understanding.

[0099] Those skilled in the art will understand that, unless otherwise specified, the order in which the steps are written in the various embodiments or methods of this application does not imply a strict execution order and does not constitute any limitation on the implementation process. The detailed execution order of each step should be determined by its function and possible internal logic. Unless otherwise specified, all steps of this application may be performed sequentially or randomly, but are preferably performed sequentially. For example, if method M includes steps (a) and (b), it means that the method may include steps (a) and (b) performed sequentially, or it may include steps (b) and (a) performed sequentially. For example, method M may also include step (c), meaning that step (c) can be added to method M in any order. For example, method M may include steps (a), (b), and (c), or it may include steps (a), (c), and (b), or it may include steps (c), (a), and (b), etc.

[0100] In this application, open-ended technical features or solutions described using terms such as "containing," "comprising," or "including" do not exclude additional members beyond those listed unless otherwise specified. They can be considered as providing both closed-ended features or solutions comprised of the listed members and open-ended features or solutions that include additional members beyond the listed members. For example, if 'a' includes a1, a2, and a3, it may also include other members or exclude additional members unless otherwise specified. This can be considered as providing both features or solutions where "a consists of a1, a2, and a3" or "a is selected from a1, a2, and a3," and features or solutions where "a includes not only a1, a2, and a3, but also other members."

[0101] In this application, unless otherwise specified, M (e.g., m1) means that m1 is a non-limiting example of M, and it is understood that M is not limited to m1.

[0102] In this application, "optionally," "optionally," and "optional" mean that something is optional, that is, it is selected from either "with" or "without." If multiple "options" appear in a technical solution, unless otherwise specified and there are no contradictions or mutual constraints, each "option" is independent. Unless otherwise specified, the descriptions such as "optionally include" and "optionally contain" in this application, taking "optionally include" as an example, mean "may include or not include."

[0103] In this application, unless otherwise specified, the features or solutions corresponding to "and / or" include any one of two or more of the related listed items, as well as any and all combinations of the related listed items. Any and all combinations include any two related listed items, any more related listed items, or a combination of all related listed items. For example, "M and / or N" represents the group consisting of M, N, and "a combination of M and N". "Containing M and / or N" can mean "containing M, containing N, and containing both M and N", or "containing M, containing N, or containing both M and N", and can be appropriately understood according to the context.

[0104] In this document, the word "suitable" in "suitable combination" or "suitable method" refers to the technical solution that can implement this application.

[0105] In this document, terms such as "preferred," "better," and "good" are merely descriptions of implementation methods or embodiments that achieve better results and should be understood not to limit the scope of protection of this application. If multiple "preferred" terms appear in a technical solution, unless otherwise specified and there are no contradictions or mutual constraints, each "preferred" term shall be independent.

[0106] In this application, terms such as "further," "even more," "especially," "for example," "as," "example," and "exemplary" are used for descriptive purposes to indicate differences in content, but should not be construed as limiting the scope of protection of this application.

[0107] In this application, the terms "first aspect," "second aspect," "third aspect," "fourth aspect," etc., are used for descriptive purposes only and should not be construed as indicating or implying relative importance or quantity, nor should they be construed as implicitly indicating the importance or quantity of the indicated technical features. Moreover, "first," "second," "third," "fourth," etc., serve only as a non-exhaustive enumeration and should be understood not to constitute a closed limitation on quantity.

[0108] In this application, the term "room temperature" generally refers to 4℃~35℃, and may refer to 20℃±5℃. In some embodiments or examples of this application, room temperature refers to 20℃~30℃.

[0109] In this application, if the unit for a data range is only followed by the right endpoint, it indicates that the units for the left and right endpoints are the same unless otherwise specified. For example, 3~5μm or 3-5μm both mean that the unit for the left endpoint "3" and the right endpoint "5" is μm (micrometer), and both have the same meaning as 3μm~5μm. Furthermore, similar descriptions of other parameters such as temperature and concentration are interpreted in the same way.

[0110] In this application, unless otherwise specified, wt% means weight percentage, which is numerically equal to the corresponding mass percentage.

[0111] In the description of the embodiments or examples of this application, the terms "center", "longitudinal", "lateral", "length", "height", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", etc., indicating the orientation or positional relationship are only for the convenience of describing the embodiments of this application and simplifying the description, and are not intended to indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation on the embodiments of this application.

[0112] In this application, unless otherwise expressly specified and limited, in the device structure, the first feature "above" or "below" the second feature can be in direct contact with the first feature, or indirect contact between the first and second features through an intermediate medium. In this application, unless otherwise expressly specified and limited, the first feature "above" or "below" the second feature can indicate a horizontal relative position, or it can simply indicate the existence of an attachment relationship without specifying a horizontal relative position.

[0113] In this application, the exemplary descriptions such as "in some implementations (or embodiments)" and "in one implementation (or embodiment)" may cover, but are not limited to, the following meanings: these solutions can be combined with other solutions in a suitable manner to form new technical solutions.

[0114] In this application, the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or quantity, nor should they be construed as implicitly indicating the importance or quantity of the indicated technical features.

[0115] Unless otherwise stated, the improvements described in this application are not intended to be limited to any theoretical constraints.

[0116] In this application, unless otherwise specified, an "optoelectronic device" is a device capable of photoelectric conversion using a photoelectric conversion mechanism, which includes the process of converting light energy into electrical energy and vice versa. An optoelectronic device can be a photovoltaic device or a light-emitting device. In this application, unless otherwise specified, the core functional layer that exchanges energy with photons can be called the "active layer," which includes a semiconductor active material. In a photovoltaic device, the semiconductor active material absorbs photons to generate carrier pairs (which are electron-hole pairs), and this active layer can be called the "light-absorbing layer" or "light-absorbing layer." In a light-emitting device, the semiconductor active material recombines injected electrons and holes and releases photons, and this active layer can be called the "light-emitting layer." Optoelectronic devices can achieve photoelectric conversion through any suitable mechanism. Photovoltaic devices can convert light energy into electrical energy based on a light-absorbing layer, and light-emitting devices can convert electrical energy into light energy based on a light-emitting layer.

[0117] In this application, unless otherwise specified, "active layer" refers to a structural layer comprising a semiconductor active material. The semiconductor active material can be any suitable type of semiconductor active material capable of photoelectric conversion. Non-limiting examples of semiconductor active materials may include one or more of perovskite materials, silicon-containing semiconductor materials, copper zinc tin sulfide, copper zinc tin selenide, copper zinc tin selenide sulfide, copper indium gallium selenide, copper indium gallium diselenide, copper indium selenide, gallium arsenide (GaAs), cadmium telluride (CdTe), and organic active materials. Exemplarily, the semiconductor active material may include one or more of perovskite materials, gallium arsenide (GaAs), cadmium telluride (CdTe), copper indium selenide (CIGS), and organic photovoltaic materials.

[0118] In this application, unless otherwise stated, a "photovoltaic device" is a photoelectric device capable of converting solar energy into electrical energy using a photoelectric conversion mechanism. The active layer in a photovoltaic device can generate carrier pairs (which can be electron-hole pairs) upon excitation by incident photons. The flow of electrons and holes generates current, thereby realizing the conversion from light energy to electrical energy. The active layer in a photovoltaic device can be referred to as a "light-absorbing layer." Application examples of photovoltaic devices may include, but are not limited to, solar cells.

[0119] In this application, unless otherwise specified, "solar cell" refers to a battery capable of converting solar energy into electrical energy using a photoelectric conversion mechanism. It is understood that a solar cell includes a light-absorbing layer. When the light-absorbing layer comprises perovskite material, the solar cell is called a "perovskite solar cell" or "perovskite battery."

[0120] In this application, unless otherwise specified, a "light-emitting device" is a photoelectric device capable of converting electrical energy into solar energy using a photoelectric conversion mechanism. The active layer in a photoelectric device can recombine injected charge carriers (electrons and holes), releasing energy in the form of photons. Non-limiting examples of light-emitting devices may include light-emitting diodes (LEDs), laser diodes (LDs), etc. Applications of light-emitting devices may include, but are not limited to, lighting and display applications.

[0121] In this application, unless otherwise specified, "energy conversion efficiency" refers to the efficiency of converting light energy (or electrical energy) into electrical energy (or light energy) in an optoelectronic device. In photovoltaic devices, energy conversion efficiency refers to the efficiency of converting light energy into electrical energy, generally referred to as photoelectric conversion efficiency (PCE). In light-emitting devices, energy conversion efficiency refers to the efficiency of converting electrical energy into light energy, which can be expressed as external quantum efficiency (EQE).

[0122] In this application, unless otherwise specified, "charge carrier" can be an electron or a hole. "Carrier pair" refers to an electron-hole pair.

[0123] In some embodiments of this application, when the photovoltaic device is operating, after the light-absorbing layer is illuminated, the internal electrons gain energy and break free from the binding force of the light-absorbing layer to form negatively charged electron carriers, and simultaneously form positively charged hole carriers, thus generating electron-hole pairs. The free electrons and free holes propagate in opposite directions, causing electrons and holes to flow and forming an external current, thereby realizing the conversion of light energy into electrical energy. Furthermore, after the light-absorbing layer absorbs photons, it is stimulated to generate electron-hole pairs. These pairs further dissociate to form free carriers with opposite charges. The free electrons propagate towards the negative electrode, and the free holes propagate towards the positive electrode. Both types of free carriers are collected by their respective electrodes, further forming a photocurrent in the circuit of the photovoltaic device.

[0124] In some embodiments of this application, in a photovoltaic device, free electrons are transported to the negative electrode through an electron transport layer, and free holes are transported to the positive electrode through a hole transport layer. The two types of free carriers are collected by their respective electrodes, and further form a photocurrent in the circuit of the photovoltaic device.

[0125] In photovoltaic devices, the electron transport layer can extract and transport electron carriers and block free holes from passing through.

[0126] In photovoltaic devices, the hole transport layer can extract and transport hole carriers and block free electrons from passing through.

[0127] In some embodiments of this application, when the light-emitting device is operating, an external forward bias voltage is applied to inject electrons from the cathode and holes from the anode. The injected charge carriers (electrons and holes) are transported to the light-emitting layer, where they recombine, releasing energy and emitting light in the form of photons. The cathode is typically connected to the negative terminal of the power supply, and the anode is typically connected to the positive terminal of the voltage.

[0128] In light-emitting devices, the electron transport layer is responsible for injecting and transporting electron carriers and can block free holes from passing through.

[0129] In light-emitting devices, the hole transport layer is responsible for injecting and transporting hole carriers and can block free electrons from passing through.

[0130] In this application, unless otherwise specified, from the perspective of the type of semiconductor active material, optoelectronic devices whose active layer includes perovskite material can be referred to as "perovskite devices". The active layer in a perovskite device can be referred to as a "perovskite layer". From an application perspective, perovskite devices can be used in both photovoltaic and light-emitting fields; that is, perovskite devices can function as both photovoltaic devices and light-emitting devices.

[0131] In this application, unless otherwise specified, "perovskite layer" refers to the active layer comprising perovskite material. The perovskite layer has a certain thickness, for example, but not limited to, 100 nm to 2000 nm.

[0132] In this application, the "thickness direction of the perovskite layer" can be denoted as the Z direction.

[0133] In this application, unless otherwise specified, the perovskite layer 100 includes two surfaces that are opposite to each other in its thickness direction (Z direction), which may be referred to as the first surface 101 and the second surface 102, respectively. (See reference...) Figure 4 The spacing between the first and second surfaces roughly corresponds to the thickness of the perovskite layer. In some embodiments of this application, the first and second surfaces of the perovskite layer respectively contact different structural layers disposed adjacent to the perovskite layer. In some embodiments, the first and second surfaces of the perovskite layer respectively contact different charge transport layers.

[0134] Optoelectronic devices can be either photovoltaic (PV) devices or light-emitting devices. A representative PV device is the perovskite solar cell, in which the light-absorbing layer is a perovskite layer containing perovskite material. Due to its high conversion efficiency and the ability to be fabricated using low-cost solution methods, perovskite solar cells have attracted widespread attention from industry. Device stability and photoelectric conversion efficiency are crucial for the practical application of perovskite solar cells. Therefore, researching ways to improve the device stability and energy conversion efficiency of optoelectronic devices is of great significance.

[0135] The most critical component of a perovskite solar cell is the light-absorbing layer, primarily composed of perovskite material. Because perovskite is an ionic crystal, its lattice structure is composed of weak ionic bonds and van der Waals interactions, making it prone to bond breakage. This leads to defects such as iodine vacancies, A-site cation vacancies, and B-site cation vacancies, affecting device stability and photoelectric conversion efficiency. Theoretically, coating the perovskite film surface with an inorganic passivator solution can passivate these defects. However, this method typically places the inorganic passivator between the perovskite layer and adjacent functional layers, only passivating that side of the perovskite layer and failing to passivate defects at grain boundaries within the perovskite layer. Adding the inorganic passivator directly to the perovskite precursor solution may result in poor solid-solid interface contact between the perovskite grains, limiting the effective passivation effect. Increasing the amount of inorganic passivator to improve passivation may lead to other adverse effects. Taking lead iodide (PbI2) particles for passivation as an example, excessive lead iodide exhibits significant photocatalytic properties, leading to accelerated degradation of perovskite under external stress conditions such as light exposure. This, in turn, results in decreased device stability and reduced long-term operational reliability. Therefore, improving the stability and energy conversion efficiency of optoelectronic devices remains a significant challenge.

[0136] According to various embodiments and examples of this application, an optoelectronic device and its fabrication method, an electrical device, and a power generation device are provided. This optoelectronic device exhibits good device stability and good energy conversion efficiency.

[0137] In some embodiments of this application, an optoelectronic device is provided, comprising a perovskite layer, wherein the perovskite layer comprises perovskite grains, and at least a portion of the outer surface of the perovskite grains are distributed with a metal element (which may be referred to as a first metal element) and iodine. Further, the first metal element may form a metal iodide with the iodine.

[0138] Unless otherwise stated in this application, the perovskite layer in the optoelectronic device includes perovskite grains.

[0139] In this application, unless otherwise specified, perovskite grains with metal iodides distributed on their outer surface may be referred to as "first perovskite grains". It is understood that the perovskite layer may also include other perovskite grains besides the first perovskite grains, that is, it may include perovskite grains without metal iodides distributed on their outer surface. Perovskite grains without metal iodides distributed on their outer surface may be referred to as "second perovskite grains".

[0140] In some embodiments of this application, an optoelectronic device is provided, which includes a perovskite layer comprising perovskite grains, wherein lead and iodine elements are distributed on the outer surface of at least a portion of the perovskite grains.

[0141] In some embodiments of this application, an optoelectronic device is provided, which includes a perovskite layer, the perovskite layer including a first perovskite grain, and lead and iodine elements are distributed on the outer surface of the first perovskite grain.

[0142] Figure 1 This is a schematic diagram showing the distribution of metal iodides in the perovskite layer of an optoelectronic device according to an embodiment of this application; metal iodides 210 are distributed on the outer surface of the first perovskite grain 110.

[0143] In some embodiments of this application, an optoelectronic device is provided, which includes a perovskite layer, the perovskite layer including perovskite grains, and at least a portion of the outer surface of the perovskite grains having metal iodides distributed thereon.

[0144] In some embodiments of this application, an optoelectronic device is provided, which includes a perovskite layer, the perovskite layer including a first perovskite grain, and a metal iodide distributed on the outer surface of the first perovskite grain.

[0145] In this application, unless otherwise stated, "metal iodide" refers to a substance composed of a first metallic element and iodine.

[0146] In some embodiments of this application, the metal iodide in the perovskite layer of the optoelectronic device has a crystalline structure.

[0147] In some embodiments of this application, an optoelectronic device is provided, comprising a perovskite layer, wherein the perovskite layer includes perovskite grains, and metal iodides are distributed on the outer surface of the perovskite grains. In the GIWAXS two-dimensional diffraction pattern of the perovskite layer, the orientation angle between the dominant crystal plane of the metal iodide and the dominant crystal plane of the perovskite grain is small, such as less than or equal to 5°. The definition and confirmation method of GIWAXS and dominant crystal planes can be found in the description in the context of this application. By controlling the angle between the dominant crystal plane of the metal iodide and the dominant crystal plane of the perovskite grain to be small, a more consistent orientation is achieved, which is beneficial to improving the effective contact between the metal iodide and the perovskite grain, thereby improving the device stability and energy conversion efficiency.

[0148] Grazing incidence wide-angle X-ray scattering (GIWAXS) and X-ray diffraction (XRD) both use X-rays for detection and obtain crystal structure and content information based on Bragg's diffraction law, but their incident angle (geometric information) and detectable depth differ significantly.

[0149] XRD technology typically penetrates samples at relatively large angles, such as several degrees (°) to tens of degrees, allowing for the detection of depths at the micrometer or even millimeter level. The acquired signal comes from the entire sample and represents the average crystallographic information of the material.

[0150] GIWAXS technology is based on grazing incidence geometry, where X-rays pass parallel to the sample surface at an extremely small angle (e.g., 0.1°~0.5°, close to the critical angle for total internal reflection). GIWAXS can detect depths from nanometers to hundreds of nanometers, enhancing and collecting signals from ultrathin surfaces. GIWAXS can also detect crystallographic information of ultrathin films.

[0151] Two-dimensional diffraction images can be obtained based on GIWAXS, which are diffraction patterns received by the detector. These two-dimensional (2D) diffraction patterns include diffraction information in all directions. Signals distributed along the horizontal direction can reflect in-plane structure information, while signals distributed along the vertical direction can reflect out-of-plane structure information.

[0152] Based on the GIWAXS 2D diffraction pattern, the following information about the thin film can be obtained:

[0153] (1) Crystal structure type or phase; the 1D spectrum obtained by conversion can be compared with the standard data of known crystal structures (such as ICSD database).

[0154] (2) Grain orientation and texture; the direction of the crystal arrangement relative to the substrate can be distinguished, and information such as whether there is a preferred orientation, preferred orientation, in-plane orientation, and out-of-plane orientation can be determined. Among them, the appearance of arc-shaped or discrete spots in the diffraction pattern indicates a preferred orientation, and the length of the arc can reflect the degree of dispersion of the orientation. The shorter the arc, the more concentrated the orientation.

[0155] (3) Interplanar spacing and lattice constant.

[0156] In this application, "crystal plane indices" can be used to distinguish different crystal planes. A crystal plane index (hkl) represents a set of parallel crystal planes with equal interplanar spacing, on which the node distribution pattern is the same. Those skilled in the art of crystallography are generally familiar with how to identify the crystal plane index of a given crystal plane. In this application, the crystal plane indices involved include, but are not limited to, (100) and (111), and the corresponding crystal planes of perovskite grains can be referred to as the (100) crystal plane and the (111) crystal plane, respectively.

[0157] In this application, unless otherwise stated, in the 2D diffraction pattern of GIWAXS, the horizontal direction corresponds to the in-plane component (q). xy This can reflect the periodic structural information parallel to the thin film surface; the vertical direction corresponds to the out-of-plane component (q). z This reflects the periodic structural information along the normal direction (perpendicular to the surface). The distance from the center position of the diffraction signal (e.g., the center position of the diffraction arc) to q... xy -q z The distance from the determined image center directly reflects the interplanar spacing of the corresponding crystal plane. Crystal planes with different crystal plane indices have different interplanar spacings. The q corresponding to the center position of the diffraction signal (such as diffraction arcs or diffraction spots) is determined by... xy and q z It can calculate lattice parameters, including interplanar spacing, and thus distinguish different types of crystal planes.

[0158] In some embodiments of the first aspect of this application, an optoelectronic device is provided, which includes a perovskite layer; the perovskite layer includes perovskite grains, and at least a portion of the outer surface of the perovskite grains is distributed with metal iodides;

[0159] In the GIWAXS two-dimensional diffraction pattern of the perovskite layer, the orientation angle between the dominant crystal plane of the metal iodide and the dominant crystal plane of the perovskite grain is less than or equal to 5°; where GIWAXS refers to grazing wide-angle X-ray scattering; the dominant crystal plane refers to the crystal plane corresponding to the strongest diffraction signal of the corresponding phase in the GIWAXS two-dimensional diffraction pattern.

[0160] In this application, unless otherwise specified, the orientation angle between the dominant crystal plane of the metal iodide and the dominant crystal plane of the perovskite grain in the GIWAXS two-dimensional diffraction pattern of the perovskite layer can be denoted as "α1".

[0161] In optoelectronic devices with a perovskite layer, by depositing a specially oriented metal iodide on the outer surface of at least a portion of the perovskite grains, the orientation angle between the dominant crystal plane of the metal iodide and the dominant crystal plane of the perovskite grain is made small (e.g., ≤5°). This allows for more effective contact between the metal iodide and the perovskite grain, thereby effectively passivating surface defects in the perovskite grains. Specifically, iodide ions in the metal iodide can passivate anionic vacancy defects on the surface of the perovskite grains, and metal ions in the metal iodide can passivate cation vacancy defects on the surface of the perovskite grains. This effectively suppresses the phenomenon of reduced degradation energy barrier of perovskite material caused by charged defect sites. In addition, the metal iodide can eliminate dangling bonds on the surface of the perovskite grains and achieve a field-effect passivation effect, forming type I / O on the surface of the perovskite grains. The band structure of I forms a grain boundary electric field, which prevents the movement of charged substances such as electrons and ions across grains, reducing or avoiding adverse phenomena such as carrier recombination and halogen phase separation. This can at least improve the energy conversion efficiency of optoelectronic devices; furthermore, reducing adverse phenomena such as halogen phase separation can further improve device stability. It is understood that we do not wish to be limited to the aforementioned theories.

[0162] In this application, unless otherwise stated, "metal iodides are distributed on the outer surface of the perovskite grains" means that the metal iodides are adjacent to the outer surface of the perovskite grains.

[0163] Unless otherwise stated in this application, the presence of metal iodides on the outer surface of perovskite grains can be confirmed by the following method: micro / nano fabrication using focused ion beam (FIE) combined with transmission electron microscopy (TEM). More specifically, FIE can be used to fabricate perovskite thin film samples or device samples to obtain cross-sectional thin layers with a thickness of less than 200 nm. Subsequently, TEM is employed, using electron diffraction to obtain lattice constants and crystal structure information, and energy-dispersive X-ray spectroscopy (EDX) to obtain elemental distribution information, thereby distinguishing between perovskite grains and metal iodides, and thus determining whether metal iodides are distributed on the outer surface of the perovskite grains. For example, high-resolution transmission electron microscopy (HRTEM) or similar instruments can be used.

[0164] The above method can also be used to determine whether metal iodides are distributed at the grain boundaries of perovskite grains.

[0165] In this application, unless otherwise specified, the crystal plane corresponding to the strongest diffraction signal of a selected phase in the GIWAXS two-dimensional diffraction pattern is defined as the "dominant crystal plane" of the corresponding phase, indicating that the crystal tends to grow along the direction of that crystal plane.

[0166] The dominant crystal planes of perovskite grains can be identified from the XRD diffraction pattern of the perovskite layer. Furthermore, the dominant crystal planes of both perovskite grains and metal iodides can be identified simultaneously from the GIWAXS two-dimensional diffraction pattern of the perovskite layer. The dominant crystal planes of the metal iodides and perovskite grains can have the same dominant orientation, meaning they can have the same type of dominant crystal planes. In this case, the azimuth angles of the dominant crystal planes of the perovskite grains and the metal iodides in the GIWAXS two-dimensional diffraction pattern are quite similar.

[0167] Unless otherwise specified, the dominant crystal plane of the perovskite grain determined by the GIWAXS two-dimensional diffraction pattern of the perovskite layer shall be referred to as the "dominant crystal plane of the perovskite grain".

[0168] Unless otherwise specified, the orientation angle (α1) between the dominant crystal plane of the metal iodide and the dominant crystal plane of the perovskite grain can be obtained as follows: In the GIWAXS 2D diffraction pattern, the angle formed by the line connecting the center of the diffraction arc and the center of the diffraction ring with the horizontal axis, i.e., the crystal's "azimuthal angle (χ)," reflects the crystal's alignment direction and crystal plane type. In the GIWAXS 2D diffraction pattern, the absolute value of the difference between the azimuthal angle (χ1) of the dominant crystal plane of the perovskite grain and the azimuthal angle (χ2) of the dominant crystal plane of the metal iodide is equal to α1.

[0169] by Figure 13 For example, the metal iodide is lead iodide, and the (100) crystal plane of the perovskite grain has the strongest diffraction peak. The dominant crystal plane of the perovskite grain is the (100) crystal plane. The dominant crystal plane of lead iodide has an azimuth angle similar to that of the dominant crystal plane of the perovskite grain, and the dominant crystal plane of lead iodide is also the (100) crystal plane.

[0170] The dominant crystal planes of different phases can also be analyzed by selective electron diffraction in transmission electron microscopy. This can identify the dominant crystal planes of perovskite grains, as well as the dominant crystal planes of metal iodides located on the outer surface or grain boundaries of perovskite grains.

[0171] The test results of selected electron diffraction in transmission electron microscopy were combined with the test analysis results of GIWAXS (see reference). Figure 13 This allows for a clearer identification of the dominant crystal faces of perovskite grains and metal iodides.

[0172] by Figure 13 For example, in the GIWAXS two-dimensional diffraction pattern of the perovskite layer, the orientation angle (α1) between the dominant crystal plane of the metal iodide and the dominant crystal plane of the perovskite grain is 2.7°.

[0173] Furthermore, according to the 2D diffraction pattern, along q xy -qz The selected angular direction in the figure can be integrated to obtain a one-dimensional (1D) integral curve, and then the peak area ratio (R1) of the dominant crystal plane of the metal iodide to that of the perovskite grain can be calculated. In some embodiments of this application, the dominant crystal plane of the metal iodide and the dominant crystal plane of the perovskite grain refer to the same type of dominant crystal plane of the metal iodide and the perovskite grain. At this point, the dominant crystal plane of the perovskite grain can be identified first based on the strongest diffraction peak in the XRD diffraction pattern of the perovskite grain. Then, the diffraction arcs corresponding to the dominant crystal planes of the perovskite grain and the metal iodide can be identified in the GIWAXS two-dimensional diffraction pattern. Furthermore, the azimuth angle of the perovskite grain can be used as the integration reference to obtain the one-dimensional (1D) integration curve of the GIWAXS two-dimensional (2D) diffraction pattern. The integrated area of ​​the diffraction peak of the dominant crystal plane of the perovskite grain (JA1) and the integrated area of ​​the diffraction peak of the dominant crystal plane of the metal iodide (JA2) can be obtained respectively, and then R1 = JA2 / JA1 × 100% can be calculated.

[0174] In some embodiments of this application, in the GIWAXS two-dimensional diffraction pattern of the perovskite layer, the orientation angle between the dominant crystal plane of the metal iodide and the dominant crystal plane of the perovskite grain is less than or equal to 5°, and may also be less than or equal to any of the following orientation angles: 0.1°, 0.2°, 0.3°, 0.4°, 0.5°, 0.6°, 0.8°, 1°, 1.2°, 1.4°, 1.5°, 1.6°, 1.8°, 2°, 2.2°, 2.4°, 2.5°, 2.6°, 2.8°, 3°, 3.5°, 4°, 4.5°, 5°, etc.

[0175] In some embodiments of this application, in the GIWAXS two-dimensional diffraction pattern of the perovskite layer, the orientation angle between the dominant crystal plane of the metal iodide and the dominant crystal plane of the perovskite grain is greater than 0 and less than or equal to 5°, and may also be greater than 0 and less than or equal to any of the following angles: 0.1°, 0.2°, 0.3°, 0.4°, 0.5°, 0.6°, 0.8°, 1°, 1.2°, 1.4°, 1.5°, 1.6°, 1.8°, 2°, 2.2°, 2.4°, 2.5°, 2.6°, 2.8°, 3°, 3.5°, 4°, 4.5°, 5°, etc.

[0176] In some embodiments of this application, in the GIWAXS two-dimensional diffraction pattern of the perovskite layer, the orientation angle between the dominant crystal plane of the metal iodide and the dominant crystal plane of the perovskite grain is less than or equal to 3°, and may also be less than or equal to any of the following orientation angles: 0.1°, 0.2°, 0.3°, 0.4°, 0.5°, 0.6°, 0.8°, 1°, 1.2°, 1.4°, 1.5°, 1.6°, 1.8°, 2°, 2.2°, 2.4°, 2.5°, 2.6°, 2.8°, 3°, etc. In this case, the angle between the dominant crystal plane of the metal iodide and the dominant crystal plane of the perovskite grain is very small, and the orientation is basically consistent, which is beneficial to further improve the effective contact between the metal iodide and the perovskite grain, thereby better improving the device stability and energy conversion efficiency.

[0177] In some embodiments of this application, the dominant crystal planes of the metal iodide are the same as those of the perovskite grains. In this case, it is beneficial for the metal iodide to contact the perovskite grains more effectively, which helps to reduce the mismatch stress at the contact point. This helps to reduce the density of interface defects, thereby reducing non-radiative recombination losses and thus providing a more stable and longer-lasting effective passivation effect.

[0178] In some embodiments of this application, the dominant crystal plane of the metal iodide and the dominant crystal plane of the perovskite grain are either (100) or (111).

[0179] Both the (100) and (111) crystal planes can be used as the preferred crystal planes for metal iodides and perovskite grains.

[0180] The perovskite layer with the (100) crystal plane as the dominant orientation has a longer photogenerated carrier lifetime and better charge transport capability. The vertically oriented (100) crystal plane can optimize the charge transport path and reduce recombination loss at the interface.

[0181] The (111) crystal plane is the close-packed plane in the cubic crystal structure of perovskite. The perovskite layer with the (111) crystal plane as the dominant orientation has a more compact arrangement of surface atoms, a larger lattice spacing, and a limited ion migration channel, which can effectively suppress phase separation in the perovskite layer. In addition, the stronger the ability to block external stress intrusion such as water vapor, the better it can combine energy conversion efficiency and device stability.

[0182] In some embodiments of this application, when the dominant crystal plane of the perovskite grain is the (100) crystal plane, the average thickness of the (100) crystal plane of the perovskite grain in the normal direction is D. (100) And 700Å≤D (100)≤1000Å. By controlling the average thickness of the (100) crystal plane of the perovskite grains in the perovskite layer in the normal direction within the above range, the growth of perovskite grains in the (100) crystal plane direction is more complete, the corresponding perovskite grain crystallinity is higher, the defects are relatively fewer, and the lattice direction of the (100) crystal plane is more matched with the migration path of charge carriers (electrons / holes), which is conducive to the transport of charge carriers along the thickness direction, reduces the scattering and recombination of charge carriers during the transport process, thereby improving the carrier mobility, improving the energy conversion efficiency and device stability of optoelectronic devices.

[0183] For example, the average thickness of the (100) crystal plane of the perovskite grain in the normal direction can be 700 Å, 750 Å, 800 Å, 850 Å, 900 Å, 950 Å, 1000 Å, or a range of values ​​selected from any two of the above values.

[0184] Furthermore, the average thickness of the (100) crystal plane of the perovskite grain in the normal direction is D. (100) Satisfying 750Å≤D (100) ≤950Å.

[0185] By controlling the average thickness of the (100) crystal plane of the perovskite grains in the perovskite layer in the normal direction within the above range, it is possible to further improve the carrier mobility and reduce the trap state density, thereby reducing the nonradiative recombination probability and further improving the energy conversion efficiency and stability of the optoelectronic device.

[0186] The term "average thickness of the (100) crystal plane in the normal direction" refers to the average thickness of crystal domains in coherent diffraction of the crystal measured along a direction perpendicular to the (100) crystal plane. For example, this can be achieved by combining X-ray diffraction (XRD) with the Scherrer equation. The equation is calculated to be: D = Kλ / (βcosθ); where D is the average thickness of the crystal plane in the normal direction (unit: Å), K is the shape factor (0.89 in this application), λ is the X-ray wavelength (unit: nm), β is the full width at half maximum (FWHM) of the diffraction peak (in radians), and θ is the diffraction angle (in radians). In this application, in the XRD pattern, the peak present at the diffraction angle 2θ of 13.9°±0.5° represents the (100) crystal plane of the perovskite grain. It can be understood that the (100) crystal plane is the dominant crystal plane here, and the diffraction peak intensity corresponding to the (100) crystal plane in the XRD pattern is the largest.

[0187] In some embodiments of this application, when the dominant crystal plane of the perovskite grain is the (111) crystal plane, the average thickness of the (111) crystal plane of the perovskite grain in the normal direction is D. (111) And 600Å≤D(111) ≤1000Å. By controlling the average thickness of the (111) crystal plane of the perovskite grains in the perovskite layer in the normal direction within the above range, the growth of perovskite grains in the (111) crystal plane direction is more complete, the corresponding perovskite grain crystallinity is higher, the defects are relatively fewer, and the atomic arrangement of the (111) crystal plane is more compact, the lattice spacing is larger, and the ion migration channels are restricted, which can effectively suppress phase separation in the perovskite layer and improve the device stability of optoelectronic devices.

[0188] For example, the average thickness of the (111) crystal plane of the perovskite grain in the normal direction can be 600 Å, 650 Å, 700 Å, 750 Å, 800 Å, 850 Å, 900 Å, 950 Å, 1000 Å, or a range of values ​​selected from any two of the above values.

[0189] In some embodiments of this application, the average thickness of the (111) crystal plane of the perovskite grain in the normal direction is D. (111) Satisfying 650Å≤D (111) ≤950Å.

[0190] By controlling the average thickness of the (111) crystal plane of the perovskite grains in the perovskite layer in the normal direction within the above range, phase separation in the perovskite layer can be further suppressed, thereby improving the device stability of optoelectronic devices.

[0191] The definition of the term "average thickness of the (111) crystal plane in the normal direction" is similar to the definition of "average thickness of the (100) crystal plane in the normal direction" mentioned above, except that the information of the (100) crystal plane is replaced with that of the (111) crystal plane. In this application, in the XRD pattern, the peak present at a diffraction angle 2θ of 24.2°±0.5° represents the (111) crystal plane of the perovskite grain. It can be understood that the (111) crystal plane is the dominant crystal plane here, and the diffraction peak intensity corresponding to the (111) crystal plane in the XRD pattern is the largest.

[0192] In some embodiments of this application, in the one-dimensional integral curve of the GIWAXS two-dimensional diffraction pattern of the perovskite layer, the ratio of the integral area of ​​the diffraction peaks of the dominant crystal plane of the metal iodide to that of the dominant crystal plane of the perovskite grain is 0.5% to 5.5%, optionally 0.5% to 5%, and may also be any of the following percentages or a range selected from any two of the following percentages: 0.5%, 0.6%, 0.8%, 1%, 1.2%, 1.4%, 1.5%, 1.6%, 1.8%, 2%, 2.2%, 2.4%, 2.5%, 2.6%, 2.8%, 3%, 3.1%, 3.2%, 3.3%, 3.4%, 3.5%, 3.7%, 4.0%, 4.2%, 4.5%, 4.8%, 5.0%, etc. At this point, the metal iodide is controlled at a low level, which can not only improve the device stability and energy conversion efficiency through effective passivation, but also significantly suppress the photocatalytic effect of metal iodide on perovskite grains. This significantly reduces the risk of accelerated degradation of perovskite grains caused by metal iodide under external stress conditions such as light, which is conducive to achieving better long-term device stability.

[0193] In some embodiments of this application, at least a portion of the metal iodide has a thickness of 20 Å to 50 Å on the outer surface of the perovskite grains, optionally 20 Å to 33 Å, or any of the following thicknesses or a range selected from any two of the following thicknesses: 20 Å, 22 Å, 24 Å, 25 Å, 26 Å, 28 Å, 30 Å, 32 Å, 33 Å, 34 Å, 35 Å, 38 Å, 40 Å, 43 Å, 45 Å, 48 Å, 50 Å, etc. In this case, the metal iodide on the outer surface of the perovskite grains is controlled to a relatively thin thickness, which is more conducive to significantly suppressing the photocatalytic effect of the metal iodide on the perovskite grains while exerting a passivation effect, and is more conducive to achieving a long-term, stable, and effective passivation effect of the metal iodide.

[0194] Focused ion beam and transmission electron microscopy (HRTEM) methods, in high-resolution mode, can be used to observe the coherence and misalignment of atoms at the interface between metal iodides and perovskite grains, and can also measure the thickness of metal iodides at the perovskite grain interface. For example, an HRTEM instrument can be used. Furthermore, it can determine whether metal iodides are distributed at the grain boundaries of perovskite grains.

[0195] For example, the thickness of the metal iodide on the outer surface of the perovskite grain can be N1 lattice sizes, with a non-limiting example of N1 being about 10 lattice sizes.

[0196] In some embodiments of this application, at least a portion of the metal iodide is located at the grain boundaries of the perovskite grains. This allows for effective connection between the perovskite grains at the grain boundaries, increasing the contact area between the metal iodide and the perovskite grains, thereby providing better passivation and further improving the energy conversion efficiency of the device.

[0197] Figure 2 This is a schematic diagram showing the distribution of metal iodides in the perovskite layer of an optoelectronic device according to an embodiment of this application; a first metal iodide 211 is distributed at the grain boundaries of the perovskite grains. "First metal iodide" refers to the metal iodide located at the grain boundaries of the perovskite grains.

[0198] Figure 3 This is a schematic diagram showing the distribution of metal iodides in the perovskite layer of an optoelectronic device according to another embodiment of this application; a first metal iodide 211 is distributed at the grain boundaries of the perovskite grains; at this time, the metal iodide 210 in the perovskite layer includes the first metal iodide 211.

[0199] In some embodiments of this application, the perovskite layer has a first surface and a second surface that are opposite to each other in the thickness direction of the perovskite layer; wherein at least a portion of the metal iodide is located on at least one of the first and second surfaces. In this case, the metal iodide can perform chemical passivation and physical passivation at the first and / or second surfaces, thereby improving the device stability and energy conversion efficiency of the optoelectronic device.

[0200] Figure 4 This is a schematic diagram showing the distribution of metal iodides in the perovskite layer of an optoelectronic device according to an embodiment of this application. Second metal iodides 212 are distributed on the first surface 101 and the second surface 102 of the perovskite layer 100, and the first surface 101 and the second surface 102 are opposite to each other in the thickness direction (i.e., the Z direction) of the perovskite layer. "Second metal iodide" refers to the metal iodide located on the first surface and / or the second surface of the perovskite layer.

[0201] Figure 5 This is a schematic diagram showing the distribution of metal iodides in the perovskite layer of an optoelectronic device according to an embodiment of this application; metal iodides are distributed at the grain boundaries of the perovskite grains and on the first surface 101 and the second surface 102 of the perovskite layer 100. At this time, the metal iodides 210 in the perovskite layer include the first metal iodide 211 and the second metal iodide 212.

[0202] In some embodiments of this application, the perovskite layer has a first surface and a second surface that are opposite to each other in the thickness direction of the perovskite layer; the content of metal iodide at the grain boundaries of the perovskite grains is higher than the sum of the contents on the first and second surfaces of the perovskite layer. In this case, the content of metal iodide at the grain boundaries is higher than the content on both sides (the first and second surfaces) of the perovskite layer. That is, more metal iodide is distributed in the perovskite bulk phase, while the content on the sides of the perovskite layer is relatively less. This not only provides a long-term, stable, and effective passivation effect but also helps to reduce the potential adverse effects of metal iodide distributed on the sides of the perovskite layer in the thickness direction on charge transport, thus improving energy conversion efficiency.

[0203] In this application, unless otherwise specified, "the distribution content of metal iodides at the grain boundaries of perovskite grains is higher than the sum of the distribution content on the first and second surfaces of the perovskite layer" can be determined using the GIWAXS standard sample calibration method.

[0204] In some embodiments of this application, perovskite grains with metal iodides distributed on the outer surface are referred to as first perovskite grains; the proportion of the first perovskite grains relative to the total number of perovskite grains in the perovskite layer is 60% to 100%, optionally 90% to 100%, and may also be any of the following percentages or a range selected from any two of the following percentages: 60%, 62%, 64%, 65%, 66%, 68%, 70%, 72%, 74%, 75%, 76%, 78%, 80%, 82%, 84%, 85%, 86%, 88%, 90%, 92%, 94%, 95%, 96%, 97%, 98%, 99%, 100%, etc.

[0205] In this application, unless otherwise stated, "the percentage of the first perovskite grain relative to the total number of perovskite grains in the perovskite layer (F)" N The following method can be used to detect and confirm the presence of perovskite grains: Randomly obtain test images of multiple perovskite layer cross-sectional regions using focused ion beam and transmission electron microscopy (high-resolution mode); count the number of first perovskite grains with metal iodide distributed on the inner and outer surfaces of the observation field, as well as the total number of perovskite grains within the field of view; and obtain the percentage of first perovskite grains in each field of view (F...). Ni Then, the F values ​​of multiple perovskite layer cross-sectional regions were analyzed. Ni Taking the average value yields F. N Value. The number of regions used is ≥10, and can be 20~50.

[0206] By controlling the proportion of the first perovskite grain relative to the total number of perovskite grains in the perovskite layer to be relatively high, more perovskite grains can be passivated by metal iodides, which is beneficial to further improve the device stability and energy conversion efficiency of optoelectronic devices.

[0207] In some embodiments of this application, the average size of the perovskite grains in the perovskite layer is 0.5 μm to 3 μm, and may also be any of the following values ​​or a range selected from any two of the following values: 0.5 μm, 0.6 μm, 0.7 μm, 0.8 μm, 0.9 μm, 1 μm, 1.1 μm, 1.2 μm, 1.3 μm, 1.4 μm, 1.5 μm, 1.6 μm, 1.8 μm, 2 μm, 2.2 μm, 2.4 μm, 2.5 μm, 2.6 μm, 2.8 μm, 3 μm, etc.

[0208] The average size of perovskite grains can be measured using a scanning electron microscope (SEM). Specifically, SEM images of the perovskite layer surface or cross-section are randomly taken at different locations on the effective subcell (non-dead zone). The longest diameter of multiple grains is manually or automatically counted using software (such as ImageJ or Nano Measure), and the average value is calculated; this average size is the perovskite grain size.

[0209] By controlling the average size of perovskite grains in the perovskite layer to be within the aforementioned relatively large range, it is beneficial to reduce the number of grain boundaries and achieve better energy conversion efficiency and device stability.

[0210] In some embodiments of this application, the metal element in the metal iodide includes one or more of lead, tin, and chromium.

[0211] In some of these embodiments, the metal element in the metal iodide includes lead.

[0212] By controlling one or more of the metal elements in the metal iodide, including lead, tin, and chromium, the ion size and valence state of these three metal elements are suitable for occupying B-site defects in the perovskite lattice. Among them, Pb also has advantages such as stable valence state and universal applicability to various band gaps; Cr and Sn ions are smaller than Pb ions, allowing for selective release of grain boundary stress caused by composition and processing, thus stabilizing grain boundaries in a third aspect—mechanical stress—in addition to chemical and physical passivation. Furthermore, Cr cations are more stable than Sn cations. 2+ It is more stable and less prone to changes in price state that could introduce additional defects.

[0213] In some embodiments of this application, the metal iodide includes lead iodide (PbI2).

[0214] In some embodiments of this application, the metal element in the metal iodide includes an ionic state. The metal element in the ionic state is a metal cation.

[0215] In some embodiments of this application, the metal iodide includes a metal cation, and further, the metal cation may include one or more of lead ions, tin ions, and ions.

[0216] In some embodiments of this application, the metal iodide includes lead ions.

[0217] It can be understood that the perovskite layer includes perovskite material (denoted as the first perovskite material).

[0218] In some embodiments of this application, the perovskite layer includes a perovskite material (referred to as the first perovskite material), which includes lead and iodine.

[0219] When the perovskite material in the perovskite layer includes lead and iodine, the Pb provided by the metal iodide... 2+ and I - It exhibits better passivation effects with lead and iodine vacancies in the perovskite layer. Furthermore, the energy level interaction between iodine and lead elements can form a suitable band gap, and the common defects in this lattice structure are all shallow energy level defects, which have a relatively small impact on the final device efficiency, thus facilitating the formation of high-efficiency devices.

[0220] In some embodiments of this application, the first perovskite material includes at least two of iodine, bromine, and chlorine.

[0221] Chloride ions promote high-quality crystallization of perovskite during the crystallization process, reducing defect density. Bromine facilitates the formation of a more stable perovskite mesophase during crystallization, resulting in perovskite with higher crystallinity. Furthermore, the addition of bromine can significantly widen the band gap of perovskite, thus benefiting its application in multilayer modules.

[0222] The anions of perovskite materials include at least two of the aforementioned halogen anions, which can combine low defect concentration and high-quality crystallization, while giving full play to the comprehensive advantages of perovskite solar cells, such as adjustable bandgap and applicability to single-junction and tandem technologies.

[0223] In some embodiments of this application, the perovskite material includes iodine anions, as well as at least one of chloride anions and other anions.

[0224] In some embodiments of this application, the perovskite material includes lead ions and iodine anions.

[0225] In this application, methods including but not limited to X-ray photoelectron spectroscopy (XPS) and time-of-flight secondary ion mass spectrometry (TOF-SIMS) can be used to obtain elemental information and elemental distribution information in different functional layers of optoelectronic devices.

[0226] X-ray photoelectron spectroscopy (XPS) can be used to obtain elemental distribution information at different depths by sputtering the sample surface layer by layer and combining it with full elemental scanning. The depth sampling depth of XPS testing is 0.5 nm to 10 nm, and it can be performed by ion sputtering (such as Ar⁺, C⁺). 0 The sample is peeled off layer by layer using either a cluster ion beam or an ion beam, and XPS full spectrum or specific elemental spectrum is acquired after each layer is peeled off. The thickness of each layer can be adjusted according to the thickness of the calcium sample. For example, when the thickness of the perovskite layer is 400 nm, information can be acquired at different perovskite layer thicknesses with intervals of 20 nm to 100 nm.

[0227] Other methods include, but are not limited to, time-of-flight secondary ion mass spectrometry (TOF-SIMS), using instruments such as PHInanoTOF Ⅲ Time-of-Flight SIMS, and allowing selection of appropriate ion sources (such as Cs). + Bi 3+ (etc.), primary ion energy (e.g., 0.5keV~30keV), imaging region size (e.g., 500×500μm) 2 100×100μm 2 Test parameters such as mass range and mass resolution, sputtering parameters (such as sputtering time, sputtering area, sputtering rate, analysis mode (such as depth profile mode, neutralization mode, etc.)) are used to obtain the three-dimensional distribution information of the corresponding elements or components in the sample to be tested.

[0228] Based on the three-dimensional distribution information of an element or component, it can be determined whether that element or component is distributed in the perovskite crystal phase. If the element or component is distributed in the perovskite crystal phase, the perovskite material can be considered to contain that element or component.

[0229] In some embodiments of this application, the perovskite layer contains a modifier, the modifier including diC 2-6 Alkylamine hydrochloride and diC 2-6 One or more of alkylamine thiocyanates.

[0230] In some of these embodiments, the modifier includes one or more of dipropylamine hydrochloride, dibutylamine hydrochloride, diethylamine thiocyanate, dipropylamine thiocyanate, dibutylamine thiocyanate, etc.

[0231] The aforementioned modulators can play a role in regulating and promoting the formation of metal iodides with advantageous orientation during the formation of perovskite layers. In the prepared optoelectronic devices, these modulators may remain at the grain boundaries, which can play a certain passivation role, passivating both cation vacancy defects and anion vacancy defects.

[0232] In this document, unless otherwise specified, "alkyl" means a monovalent residue formed by the loss of a hydrogen atom from a saturated hydrocarbon containing a primary (normal) carbon atom, or a secondary carbon atom, or a tertiary carbon atom, or a quaternary carbon atom, or a combination thereof. Phrases containing this term, such as "C1-6 alkyl," refer to alkyl groups containing 1 to 6 carbon atoms, and each time it appears, it can be independently referred to as C1 alkyl, C2 alkyl, C3 alkyl, C4 alkyl, C5 alkyl, or C6 alkyl. Suitable examples include, but are not limited to: methyl (Me, -CH3), ethyl (Et, -CH2CH3), 1-propyl (n-Pr, n-propyl, -CH2CH2CH3), 2-propyl (i-Pr, i-propyl, -CH(CH3)2), 1-butyl (n-Bu, n-butyl, -CH2CH2CH2CH3), 2-methyl-1-propyl (i-Bu, i-butyl, -CH2CH(CH3)2), 2-butyl (s-Bu, s-butyl, -CH(CH3)CH2CH3), 2-methyl-2-propyl (t-Bu, t-butyl, -C(CH3)3), 1-pentyl (n-pentyl, -CH2CH2CH2CH2CH3), 2-pentyl (-CH( CH3)CH2CH2CH3), 3-pentyl (-CH(CH2CH3)2), 2-methyl-2-butyl (-C(CH3)2CH2CH3), 3-methyl-2-butyl (-CH(CH3)CH(CH3)2), 3-methyl-1-butyl (-CH2CH2CH(CH3)2), 2-methyl-1-butyl (-CH2CH(CH3)CH2CH3), 1-hexyl (-CH2CH2CH2CH2CH2CH3), 2-hexyl (-CH(CH3)CH2CH2CH2CH3), 3-hexyl (-CH(CH2CH3)(CH2CH2CH3)), 2-methyl-2-pentyl (-C(CH3)2CH2CH2CH3).

[0233] Unless otherwise stated herein, "C" in any implementation method refers to... 1-6 "alkyl" can be C 1-4 Alkyl groups, which can further be C16-264 ... 1-3 Alkyl groups, as non-limiting examples, include methyl, ethyl, propyl (e.g., n-propyl) or butyl (e.g., n-butyl).

[0234] In some embodiments of this application, the area of ​​the perovskite layer is greater than or equal to 0.09 cm² in the direction perpendicular to the thickness of the perovskite layer.2 In this case, the passivation scheme provided by the aforementioned embodiments can exert a more significant advantage in relatively large-sized devices.

[0235] In some embodiments of this application, the area of ​​the perovskite layer in the direction perpendicular to the thickness of the perovskite layer may be any of the following values, or greater than or equal to any of the following values, or selected from a range consisting of any two of the following values: 0.09 cm 2 0.1 cm 2 0.12 cm 2 0.125 cm 2 0.15 cm 2 0.16 cm 2 0.175 cm 2 0.18cm 2 0.2 cm 2 0.22 cm 2 0.225 cm 2 0.25 cm 2 1 cm 2 4 cm 2 9 cm 2 10 cm 2 16 cm 2 20 cm 2 25cm 2 36 cm 2 49 cm 2 50 cm 2 60 cm 2 64 cm 2 65 cm 2 70 cm 2 80 cm 2 81 cm 2 90 cm 2 100cm 2 120 cm 2 121 cm 2 125 cm 2 130 cm 2 140 cm 2 144 cm 2 150 cm 2 160 cm 2 169 cm 2 170cm 2 180 cm 2 190 cm 2 196 cm 2、200 cm 2 、225 cm 2 、250 cm 2 、256 cm 2 、260 cm 2 、280 cm 2 、289cm 2 、290 cm 2 、300 cm 2 、320 cm 2 、324 cm 2 、325 cm 2 、330 cm 2 、350 cm 2 、360 cm 2 、361 cm 2 、370cm 2 、380 cm 2 、400 cm 2 、440 cm 2 、441 cm 2 、450 cm 2 、480 cm 2 、484 cm 2 、500 cm 2 、600 cm 2 、625cm 2 、660 cm 2 、676 cm 2 、680 cm 2 、700 cm 2 、720 cm 2 、729 cm 2 、730 cm 2 、780 cm 2 、784 cm 2 、800cm 2 、820 cm 2 、840 cm 2 、841 cm 2 、850 cm 2 、860 cm 2 、900 cm 2 、950 cm 2 、961 cm 2 、980 cm 2 、0.1m 2 、0.12 m 2 、0.14 m 2 、0.15 m 2 、0.16 m2 0.18 m 2 0.2 m 2 0.3 m 2 0.4 m 2 0.5 m 2 0.6 m 2 0.7m 2 0.8 m 2 0.9 m 2 10000 cm 2 (1 m 2 ), 1.1 m 2 1.2 m 2 1.3 m 2 1.4 m 2 1.5 m 2 1.6 m 2 1.7m 2 1.8 m 2 1.9 m 2 2 m 2 2.1 m 2 2.2 m 2 2.3 m 2 2.4 m 2 2.5 m 2 2.6 m 2 2.7 m 2 2.8 m 2 2.9m 2 3 m 2 3.2 m 2 3.4 m 2 3.5 m 2 3.6 m 2 3.7 m 2 3.8 m 2 4 m 2 4.2 m 2 4.4 m 2 4.5 m 2 wait.

[0236] By setting metal iodides with a small preferred orientation angle on the surface of perovskite grains through the aforementioned embodiments, grain boundary passivation can be uniformly and effectively carried out over a large area when the perovskite layer area is large. This provides a stable and long-term effective passivation effect, which is beneficial to improving the energy conversion efficiency and device stability of large-area devices.

[0237] In some embodiments of this application, the optoelectronic device includes a first electrode and a second electrode, with a perovskite layer located between the first electrode and the second electrode.

[0238] In optoelectronic devices, one of the first electrode and the second electrode is a positive electrode, and the other is a negative electrode.

[0239] In optoelectronic devices, at least one of the first electrode and the second electrode is a transparent electrode. Either transparent electrode can be used for light incident.

[0240] In optoelectronic devices, both the first electrode and the second electrode are transparent electrodes.

[0241] In the thickness direction of the perovskite layer, for an optoelectronic device, when light can be incident from only one side, that side is denoted as the "incident side"; when light can be incident from both sides of the optoelectronic device, the side with higher device efficiency (PCE) for light incident is defined as the "incident side". Correspondingly, unless otherwise specified, if the first and second electrodes consist of only one transparent electrode, that transparent electrode is defined as the "incident side electrode". If the optoelectronic device includes two transparent electrodes, the transparent electrode with higher device efficiency (PCE) for light incident on the corresponding transparent electrode is defined as the "incident side electrode". In this case, the other electrode can be defined as the "back electrode".

[0242] It is understood that the incident light-side electrode is a transparent electrode. The back electrode may or may not be a transparent electrode; for example, the back electrode may be a metal electrode. The meanings of transparent electrode and metal electrode are well known to those skilled in the art, and their implications are understandable.

[0243] In some embodiments of this application, one of the "first electrode" and the "second electrode" is a transparent electrode for light incident. In some embodiments, the first electrode is a transparent electrode.

[0244] In some embodiments of this application, the second electrode is a metal electrode.

[0245] In some embodiments of this application, the first electrode is a transparent electrode and the second electrode is a metal electrode.

[0246] In some embodiments of this application, the optoelectronic device includes a photovoltaic device or a light-emitting device. The aforementioned perovskite layer can be used in photovoltaic devices or light-emitting devices, which helps to improve the energy conversion efficiency and device stability of photovoltaic devices or light-emitting devices.

[0247] In some embodiments of this application, the optoelectronic device is a photovoltaic device, which includes a solar cell; the solar cell includes a perovskite layer.

[0248] The aforementioned perovskite layer can be incorporated into solar cells to improve the photoelectric conversion efficiency and device stability of solar cells.

[0249] In some embodiments of this application, the optoelectronic device is a photovoltaic device, which includes a multi-junction solar cell.

[0250] In this application, unless otherwise specified, a "multi-junction solar cell" refers to a solar cell in which two or more cell cells made of semiconductor active materials with different band gaps are stacked together in series optically and / or electrically. Multi-junction solar cells can broaden the absorption spectrum of solar cells, maximizing the conversion of light energy into electrical energy, and also help reduce thermal relaxation losses. Multi-junction solar cell design is an important way to overcome the Shockley-Queisser limit efficiency of single-junction solar cells. A multi-junction solar cell includes at least two cell cells, each cell cell including at least one light-absorbing layer, and each light-absorbing layer has a different band gap.

[0251] It is understandable that a "cell" in a multi-junction solar cell includes at least a light-absorbing layer. The light-absorbing layers in different cells can provide different band gaps.

[0252] In this application, unless otherwise specified, "battery cell" and "battery section" have the same meaning and can be used interchangeably.

[0253] In this application, unless otherwise specified, "light-absorbing layer" and "light-absorbing layer" have the same meaning and can be used interchangeably.

[0254] In this application, unless otherwise specified, "band gap" has a commonly known meaning in the art and can be analyzed, compared, and confirmed using conventional methods within the art. Without limitation, the band gap of a material can be determined by its absorption or emission spectra; commonly used optical methods include ultraviolet-visible absorption spectroscopy, photoluminescence spectroscopy, and Raman spectroscopy.

[0255] When solar cells are multi-junction solar cells, they are beneficial for improving the utilization rate of incident light, while also possessing the aforementioned advantages of high photoelectric conversion efficiency and high device stability. Multi-junction solar cells can be monolithic integrated tandem solar cells or mechanically tandem solar cells, offering flexibility in form and a wide range of applications.

[0256] In some embodiments of this application, the optoelectronic device includes a solar cell, which is a multi-junction solar cell. The multi-junction solar cell includes a first cell unit, which includes a light-absorbing layer (which may be referred to as a first light-absorbing layer or first light-absorbing layer). The first light-absorbing layer may include the aforementioned perovskite layer.

[0257] In some embodiments of this application, the first light-absorbing layer is the aforementioned perovskite layer.

[0258] The aforementioned perovskite layer can be incorporated into multi-junction solar cells to improve the photoelectric conversion efficiency and device stability of multi-junction solar cells.

[0259] In some embodiments of this application, the multijunction solar cell further includes a second cell stacked with the first cell cell; the second cell cell and the first cell cell are connected by an interconnect layer, or the second cell cell and the first cell cell are isolated by an insulating layer; the second cell cell includes a light absorption layer (which may be referred to as the second light absorption layer or the second light-absorbing layer), and the second light absorption layer and the first light absorption layer have different band gaps.

[0260] In some embodiments of this application, the interconnect layer includes a carrier recombination layer or a tunneling layer. In some embodiments, the interconnect layer can be a carrier recombination layer or a tunneling layer.

[0261] In some embodiments of this application, the band gaps of the second light-absorbing layer and the perovskite layer are different.

[0262] In this way, by setting up multiple light-absorbing layers with different band gaps, multi-junction solar cells can effectively absorb light of different wavelengths, broaden the spectral range of light absorbed by multi-junction solar cells, and improve the photoelectric conversion efficiency of multi-junction solar cells.

[0263] In some embodiments, the multijunction solar cell is a tandem solar cell.

[0264] In some embodiments of this application, the second light-absorbing layer in the second battery cell includes a semiconductor active material (which may be referred to as the second semiconductor active material). The second semiconductor active material includes one or more of the following: a second perovskite material, a silicon-containing semiconductor material, a copper zinc tin sulfide, a copper zinc tin selenide, a copper zinc tin selenide sulfide, a copper indium gallium selenide, a copper indium gallium diselenide, a copper indium selenide, cadmium telluride, gallium arsenide, and organic active materials.

[0265] The aforementioned embodiments can be universally applied to the aforementioned different types of multi-junction solar cells.

[0266] In some embodiments of this application, a carrier recombination layer or a tunneling layer is provided between the monolithically integrated battery cells.

[0267] In this application, unless otherwise specified, the "carrier recombination layer" is a structural layer in which electrons and holes transported from two different battery cells recombine, enabling the two battery cells to achieve ohmic connection and share the positive and negative electrodes.

[0268] In some embodiments of this application, a carrier recombination layer is provided between the first battery cell and the second battery cell.

[0269] In some embodiments of this application, interconnection structures are provided between the battery cells connected in series, which can provide tunneling junctions (also known as tunneling layers) to realize tunneling conduction and electrical series connection between different battery cells, while maintaining optical transparency so that photons can pass smoothly through the previous battery cell to the next battery cell.

[0270] In some embodiments of this application, an interconnection structure is provided between the first battery cell and the second battery cell.

[0271] In some embodiments of this application, a tunnel junction may be formed between the first battery cell and the second battery cell.

[0272] In some embodiments of this application, the charge carrier recombination layer is a structural layer in which electrons transported from the first battery cell and holes transported from the second battery cell recombine, or in which holes transported from the first battery cell and electrons transported from the second battery cell recombine, thereby connecting the first battery cell and the second battery cell in series.

[0273] In some embodiments of this application, a multi-junction solar cell includes a first electrode, a perovskite layer, an interconnect layer, a light-absorbing layer, and a second electrode stacked together. A carrier recombination layer or tunneling layer is located between the perovskite layer and the light-absorbing layer. The first electrode is located on the side of the perovskite layer facing away from the interconnect layer, and the second electrode is located on the side of the light-absorbing layer facing away from the interconnect layer. Thus, two cell units in a multi-junction solar cell are connected through the interconnect layer to achieve current matching between the two cell units. This results in a relatively smaller size, the ability to absorb light of different wavelengths, a wider absorption spectrum range for the multi-junction solar cell, and an improved photoelectric conversion efficiency. The interconnect layer includes a carrier recombination layer or a tunneling layer.

[0274] In some embodiments of this application, a multi-junction solar cell includes a first electrode, a perovskite layer, a third electrode, an insulating layer, a fourth electrode, a light-absorbing layer, and a second electrode stacked together. The third electrode, insulating layer, and fourth electrode are stacked between the perovskite layer and the light-absorbing layer. The third electrode is located on the side of the insulating layer facing the perovskite layer, and the fourth electrode is located on the side of the insulating layer facing the light-absorbing layer. The first electrode is located on the side of the perovskite layer away from the third electrode, and the second electrode is located on the side of the light-absorbing layer away from the fourth electrode. Thus, the multi-junction solar cell forms a mechanically stacked cell. The insulating layer isolates the two cell units, preventing direct conduction of charge carriers and eliminating the need for current matching. Furthermore, each cell has its own independent positive and negative electrodes for current extraction, allowing for flexible circuit adjustments.

[0275] In this application, unless otherwise specified, a multi-junction solar cell with two battery cells may also be referred to as a "tandem solar cell". A tandem solar cell may be a two-terminal structure or a four-terminal structure.

[0276] In some embodiments of this application, the tandem solar cell has a two-end structure. In this case, two cell units are directly connected in series through a tunneling layer or a carrier recombination layer. The tandem solar cell only has two output electrodes, one positive and the other negative, and the current between the two cell units remains consistent. This type of tandem solar cell can also be called a monolithic integrated tandem cell, which refers to cell units stacked along the thickness direction that are electrically connected in series between a pair of electrode layers. Different cell units are connected through a carrier recombination layer or a tunneling layer to achieve current matching between adjacent cell units, so that adjacent cell units form an integrated structure of electrical and optical series connection.

[0277] In some embodiments of this application, the tandem solar cell includes a first electrode, a first light-absorbing layer, a carrier recombination layer, a second light-absorbing layer, and a second electrode. The first light-absorbing layer and the second light-absorbing layer are respectively disposed on both sides of the carrier recombination layer. The first electrode is located on the side of the first light-absorbing layer away from the carrier recombination layer, and the second electrode is located on the side of the second light-absorbing layer away from the carrier recombination layer.

[0278] In some embodiments of this application, the tandem solar cell includes a first electrode, a first light-absorbing layer, a tunneling layer, a second light-absorbing layer, and a second electrode. The first light-absorbing layer and the second light-absorbing layer are respectively disposed on both sides of the tunneling layer. The first electrode is located on the side of the first light-absorbing layer away from the tunneling layer, and the second electrode is located on the side of the second light-absorbing layer away from the tunneling layer.

[0279] In some embodiments of this application, the tandem solar cell has a four-terminal structure. In this case, the cell cells are electrically independent and operate independently, with coupling between the cell cells only through optical means; no carrier recombination layer or tunneling layer is provided between the cell cells. Each cell cell has its own pair of electrodes (positive and negative), and the entire tandem solar cell has four electrical output terminals, corresponding to the four electrodes. Two cell cells are isolated in the stacking direction by an insulating layer to prevent short circuits between the two cell cells.

[0280] In some embodiments of this application, the optoelectronic device is a photovoltaic device; the optoelectronic device satisfies one or more of the following characteristics:

[0281] (a1) The perovskite layer is contained in the inverse or formal structure of the optoelectronic device;

[0282] (a2) The optoelectronic device includes a first charge transport layer and a second charge transport layer, and a perovskite layer is stacked between the first charge transport layer and the second charge transport layer; wherein, one of the first charge transport layer and the second charge transport layer is a hole transport layer and the other is an electron transport layer.

[0283] The aforementioned implementation methods can be universally applied to photovoltaic devices with formal or inverted structures, thereby improving photoelectric conversion efficiency and device stability.

[0284] Furthermore, the aforementioned advantages of the perovskite layer do not depend on the positional relationship between the hole transport layer and the electron transport layer stacked with the perovskite layer, and can be utilized in devices with different structures.

[0285] In some implementations, the bandgap of the perovskite layer (i.e., the first light-absorbing layer) is Eg2, where 1.65 eV ≤ Eg2 ≤ 2.2 eV; the bandgap of the second light-absorbing layer is Eg1, where 1.1 eV ≤ Eg1 ≤ 1.6 eV. This bandgap configuration of the perovskite layer and the second light-absorbing layer effectively absorbs both short-wavelength and long-wavelength light, improving the photoelectric conversion efficiency of the multi-junction solar cell. In this implementation, the cell unit corresponding to the second light-absorbing layer is a narrow-bandgap solar cell, and the cell unit corresponding to the perovskite layer is a wide-bandgap solar cell.

[0286] In some embodiments, the second light-absorbing layer comprises a layer of compounds including: a second perovskite material, a silicon-containing semiconductor material, copper zinc tin sulfide, copper zinc tin selenide, copper zinc tin selenide sulfide, copper indium gallium selenide, copper indium gallium diselenide, copper indium selenide, cadmium telluride, gallium arsenide, and organic active materials. These materials can absorb light of different wavelengths with the perovskite layer, thereby broadening the spectral range of light absorption in the multi-junction solar cell and improving its photoelectric conversion efficiency. In some embodiments of this application, the definition of the second perovskite material is the same as that of the first perovskite material, but the composition differs to obtain a second light-absorbing layer with a different bandgap, used to absorb light of different wavelengths with the perovskite layer, broadening the absorption spectral range of the multi-junction solar cell and improving its photoelectric conversion efficiency. Exemplarily, the second light-absorbing layer comprises a second perovskite material, thereby obtaining a perovskite-perovskite multi-junction solar cell. In another example, the second light-absorbing layer comprises a crystalline silicon material, thereby obtaining a perovskite-crystalline silicon multi-junction solar cell.

[0287] Organic active materials are typically composed of blends of electron donor and electron acceptor materials. Common electron donor materials include poly(3-hexylthiophene) (P3HT), wide-bandgap polymer donor PM6, and high-efficiency polymer donor D18, while common electron acceptor materials include fullerene acceptors (such as PC). 61 BM, PC71 BM, etc.), and non-fullerene acceptors (such as Y6 series materials, indendrothiophene derivatives, BTP series, etc.). Exemplary organic active materials include PM6:Y6 and P3HT:PC. 61 One of BM, D18:BTP-eC9, etc. can be used to obtain multiple types.

[0288] In some embodiments, a multi-junction solar cell includes a first electrode and a second electrode, with a first light-absorbing layer and a second light-absorbing layer both located between the first electrode and the second electrode, the first light-absorbing layer being closer to the first electrode and the second light-absorbing layer being closer to the second electrode.

[0289] In some implementations, the first electrode in a multi-junction solar cell is a transparent electrode. This allows light to enter the multi-junction solar cell from the first electrode. Furthermore, the band gap of the second light-absorbing layer is Eg1, 1.1 eV ≤ Eg1 ≤ 1.6 eV; the band gap of the perovskite layer is Eg2, 1.65 eV ≤ Eg2 ≤ 2.2 eV. Thus, light entering from the first electrode first passes through the perovskite layer, where it absorbs short-wavelength light (such as ultraviolet to visible light), and then enters the second light-absorbing layer, where it absorbs longer-wavelength light (such as near-infrared light). This allows for greater utilization of different wavelengths of light, improving the photoelectric conversion efficiency of the multi-junction solar cell. Furthermore, the perovskite layer, acting as the top light-absorbing layer, absorbs ultraviolet-visible light, protecting the second light-absorbing layer, which acts as the bottom light-absorbing layer.

[0290] In other embodiments, the bandgap of the second light-absorbing layer is Eg3, where 1.65 eV ≤ Eg3 ≤ 2.2 eV; and the bandgap of the perovskite layer is Eg4, where 1.1 eV ≤ Eg4 ≤ 1.6 eV. Thus, the bandgap settings of the second light-absorbing layer and the perovskite layer can absorb short-wavelength and long-wavelength light respectively, improving the photoelectric conversion efficiency of the multi-junction solar cell. In this embodiment, the cell unit corresponding to the second light-absorbing layer is a wide-bandgap solar cell, and the cell unit corresponding to the perovskite layer is a narrow-bandgap solar cell.

[0291] In other embodiments, the second light-absorbing layer comprises a third perovskite material. Thus, the resulting multi-junction solar cell is a perovskite-perovskite multi-junction solar cell. In some embodiments of this application, the third perovskite material is defined as the same type as the first perovskite material described above, but with a different composition to obtain a second light-absorbing layer with a different bandgap. This layer is used to absorb light of different wavelengths with the perovskite layer, broadening the absorption spectrum range of the multi-junction solar cell and improving its photoelectric conversion efficiency. Exemplarily, the third perovskite material includes APbI. z Br 3-z The material shown is defined as above, where 0 < z < 3.

[0292] In other embodiments, the second electrode in a multi-junction solar cell is a transparent electrode. This allows light to enter the multi-junction solar cell through the second electrode. Furthermore, the band gap of the second light-absorbing layer is Eg3, 1.65 eV ≤ Eg3 ≤ 2.2 eV; the band gap of the perovskite layer is Eg4, 1.1 eV ≤ Eg4 ≤ 1.6 eV. Thus, light entering from the second electrode first passes through the second light-absorbing layer, which absorbs short-wavelength light (such as ultraviolet to visible light), and then enters the perovskite layer, where it absorbs longer-wavelength light (such as near-infrared light). This allows for greater utilization of different wavelengths of light, improving the photoelectric conversion efficiency of the multi-junction solar cell. Furthermore, the second light-absorbing layer, acting as the top cell's light-absorbing layer, absorbs ultraviolet-visible light, protecting the perovskite layer as the bottom cell's light-absorbing layer.

[0293] In some implementations, a multi-junction solar cell includes a first electrode, a perovskite layer, a carrier recombination layer or tunneling layer, a second light-absorbing layer, and a second electrode stacked together, with the carrier recombination layer or tunneling layer located between the perovskite layer and the second light-absorbing layer. In this way, the multi-junction solar cell forms a monolithic integrated tandem cell, with two cell units connected by the carrier recombination layer or tunneling junction to achieve current matching between the two cell units. It has a relatively smaller size, can absorb light of different wavelengths, broadens the absorption spectrum range of the multi-junction solar cell, and improves the photoelectric conversion efficiency of the multi-junction solar cell.

[0294] In some embodiments, a multijunction solar cell includes a first electrode, a perovskite layer, a tunneling layer, a second light-absorbing layer, and a second electrode stacked together, with the tunneling layer located between the perovskite layer and the second light-absorbing layer.

[0295] In some implementations, a multijunction solar cell includes a first charge transport layer, a second charge transport layer, a third charge transport layer, and a fourth charge transport layer.

[0296] In this application, the first charge transport layer, the second charge transport layer, the third charge transport layer, and the fourth charge transport layer are used to transport the first charge carrier, the second charge carrier, the third charge carrier, and the fourth charge carrier, respectively. One of the first charge carrier and the second charge carrier is an electron and the other is a hole. One of the third charge carrier and the fourth charge carrier is an electron and the other is a hole.

[0297] In some embodiments, a multi-junction solar cell includes a first electrode, an optional first charge transport layer, a perovskite layer, an optional second charge transport layer, a carrier recombination layer or a tunneling layer, an optional third charge transport layer, a second light absorption layer, an optional fourth charge transport layer, and a second electrode, all stacked together. Where the first to fourth charge carriers are present, the first and third charge transport layers are identical and selected from either an electron transport layer or a hole transport layer, and the second and fourth charge transport layers are identical and selected from either an electron transport layer or a hole transport layer. Thus, a first electrode, an optional first charge transport layer, a perovskite layer, and an optional second charge transport layer form a first battery cell; an optional third charge transport layer, a second light absorption layer, an optional fourth charge transport layer, and a second electrode form a second battery cell. A carrier recombination layer is used to recombine and annihilate electrons generated from the perovskite layer and holes generated from the second light absorption layer (or holes generated from the perovskite layer and electrons generated from the second light absorption layer) that are transported towards the carrier recombination layer, thereby achieving low-ohmic tunnel recombination between the first battery cell containing the perovskite layer and the second battery cell containing the second light absorption layer, ensuring the connectivity between the two battery cells. A tunneling layer is located between the two battery cells, and its main function is to achieve efficient transport of electrons and holes. Through the tunneling effect, the tunneling layer allows electrons and holes to be transported from the bottom battery to the top battery, thereby reducing energy loss due to electron thermal relaxation and improving the photoelectric conversion efficiency of the battery. Exemplarily, the second light absorption layer includes a second perovskite material, thus resulting in a perovskite-perovskite multi-junction solar cell. In another example, the second light-absorbing layer comprises crystalline silicon, thereby resulting in a perovskite-crystalline silicon multijunction solar cell.

[0298] In some embodiments of this application, multi-junction solar cells may include all four charge transport layers simultaneously, or may include only one or more of them; this is not limited here. The presence of charge transport layers helps to extract and transport electrons or holes generated by the perovskite layer or the second light-absorbing layer, enhancing the extraction and transport effect of electrons and holes and improving the performance of the multi-junction solar cell. The materials for the corresponding electron transport layer and hole transport layer are selected as defined above; the materials for the electron transport layer or hole transport layer corresponding to the first and second cell units may be the same or different.

[0299] In some embodiments, a multi-junction solar cell includes a first electrode, a hole transport layer, a perovskite layer, an electron transport layer, a carrier recombination layer or a tunneling layer, an optional hole transport layer, a second light absorption layer, an optional electron transport layer, and a second electrode, all stacked together.

[0300] In this application, the carrier recombination layer comprises one or more of the following: metallic materials, transparent conductive oxides, and carbon materials. Further, the transparent conductive oxide layer comprises, but is not limited to, one or more of the following: fluorine-doped tin oxide (FTO), indium tin oxide (ITO), aluminum-doped zinc oxide (AZO), boron-doped zinc oxide (BZO), indium zinc oxide (IZO), tungsten-doped indium oxide (IWO), indium gallium zinc oxide (IGZO), and antimony-doped tin oxide (ATO). Further, the metallic materials include, but are not limited to, one or more of the following: gold, copper, silver, platinum, aluminum, and iron. Further, the carbon materials include, but are not limited to, one or more of the following: graphite, graphene, and carbon nanotubes.

[0301] In some implementations, the thickness of the carrier recombination layer is 0.1 nm to 200 nm. For example, it can be 0.1 nm, 0.8 nm, 1 nm, 2 nm, 10 nm, 30 nm, 50 nm, 90 nm, 100 nm, 130 nm, 150 nm, 160 nm, 200 nm, or any two of the above values ​​as endpoints.

[0302] In some implementations, the components of the tunneling layer include, but are not limited to, PEDOT, transparent metal oxides, etc.

[0303] In other embodiments, a multi-junction solar cell includes a first electrode, a perovskite layer, a third electrode, an insulating layer, a fourth electrode, a second light-absorbing layer, and a second electrode stacked together. The third electrode, insulating layer, and fourth electrode are stacked between the perovskite layer and the second light-absorbing layer. The third electrode is positioned on the side of the insulating layer facing the perovskite layer, and the fourth electrode is positioned on the side of the insulating layer facing the second light-absorbing layer. In this way, the multi-junction solar cell forms a mechanically stacked cell. The insulating layer isolates the two cell units, preventing direct parallel connection of charge carriers and eliminating the need for current matching. Furthermore, each cell unit has its own independent positive and negative electrodes for current extraction, allowing for flexible circuit adjustments.

[0304] In some embodiments, a multi-junction solar cell includes a first electrode, an optional fifth charge transport layer, a perovskite layer, an optional sixth charge transport layer, a third electrode, an insulating layer, a fourth electrode, an optional seventh charge transport layer, a second light-absorbing layer, an optional eighth charge transport layer, and a second electrode stacked together. The fifth charge transport layer is selected from either a hole transport layer or an electron transport layer; the sixth charge transport layer is selected from either a hole transport layer or an electron transport layer different from the fifth charge transport layer; the seventh charge transport layer is selected from either a hole transport layer or an electron transport layer; and the eighth charge transport layer is selected from either a hole transport layer or an electron transport layer different from the seventh charge transport layer. The definitions and material selections of the corresponding hole transport layers or electron transport layers are as described above and will not be repeated here. Thus, a first electrode, optionally a fifth charge transport layer, a perovskite layer, optionally a sixth charge transport layer, and a third electrode form a first battery cell; a fourth electrode, optionally a seventh charge transport layer, a second light-absorbing layer, optionally an eighth charge transport layer, and a second electrode form a second battery cell. The first and second battery cells are electrically isolated by an insulating layer. Each battery cell has two electrodes, for a total of four electrodes. The circuits of the two battery cells are independent of each other, forming a four-terminal multi-junction solar cell. This allows for adjustment of the current in the multi-junction solar cell. Exemplarily, the second light-absorbing layer comprises a second perovskite material, resulting in a perovskite-perovskite multi-junction solar cell. In another example, the second light-absorbing layer comprises crystalline silicon, resulting in a perovskite-crystalline silicon multi-junction solar cell.

[0305] Furthermore, since the third and fourth electrodes are located in the middle of the multi-junction solar cell, in order to further increase the light energy utilization of the multi-junction solar cell and enable the remaining light after absorption by one cell to enter the next cell, the third and fourth electrodes can be set as light-transmitting electrodes, and the materials can be selected from one or more of the above-mentioned transparent conductive oxides.

[0306] In some embodiments, the material of the insulating layer includes, but is not limited to, glass or an insulating adhesive. Further, the glass is transparent glass; further, the insulating adhesive is a transparent adhesive.

[0307] In some embodiments, the multi-junction solar cell may also include multi-junction solar cells composed of 3, 4, or 5 cells, such as 3-junction solar cells, 4-junction solar cells, 5-junction solar cells, etc., and may be mechanically stacked cells, monolithically integrated stacked cells, or hybrid stacked cells composed of both, without limitation here.

[0308] In some embodiments of this application, the optoelectronic device 10 includes a perovskite layer 110 and a charge transport layer 300 stacked together, as can be seen in the following references. Figure 6 Furthermore, Figure 6The charge transport layer shown can be either an electron transport layer or a hole transport layer. Figure 6 The perovskite layer and charge transport layer are arranged adjacently. It can be understood that other functional layers, such as passivation layers, barrier layers, buffer layers, interface layers, etc., can also be arranged at the interface between the perovskite layer and the charge transport layer. The charge transport layer can be the appropriate first charge transport layer described in the context.

[0309] In some embodiments of this application, the optoelectronic device 10 includes a first charge transport layer 310, a perovskite layer 100, and a second charge transport layer 320 stacked together. The first charge transport layer 310 and the second charge transport layer 320 are respectively disposed on opposite sides of the perovskite layer 100 in the thickness direction (Z direction) of the perovskite layer. (See reference...) Figure 7 It can be seen that... Figure 7 The perovskite layer and the first charge transport layer and the second charge transport layer located on both sides are respectively disposed adjacent to each other. It can be understood that the first charge transport layer and the second charge transport layer can be disposed independently without being adjacent to the perovskite layer. For example, other functional layers, such as one or more of the following, can be disposed between at least one of the first charge transport layer and the second charge transport layer and the perovskite layer: passivation layer, barrier layer, buffer layer, interface layer, etc.

[0310] In some embodiments of this application, the optoelectronic device includes a first electrode and a second electrode, with a perovskite layer and a charge transport layer stacked between the first electrode and the second electrode.

[0311] In some embodiments of this application, the optoelectronic device includes a first electrode and a second electrode. The first electrode is located on the side of the first charge transport layer away from the perovskite layer, and the second electrode is located on the side of the light-absorbing layer away from the first charge transport layer. The first charge transport layer can be an electron transport layer or a hole transport layer. In some embodiments, the optoelectronic device further includes a second charge transport layer located between the perovskite layer and the second electrode.

[0312] In some embodiments of this application, the optoelectronic device includes a first charge transport layer and a second charge transport layer, wherein the first charge transport layer and the second charge transport layer are located on opposite sides of the perovskite layer in the thickness direction of the perovskite layer. Further, one of the first charge transport layer and the second charge transport layer is an electron transport layer, and the other is a hole transport layer. In some embodiments, the first charge transport layer is a hole transport layer. In other embodiments, the first charge transport layer is an electron transport layer.

[0313] Figure 8This is a schematic diagram of the structure of an optoelectronic device according to one embodiment of this application. The optoelectronic device 10 includes a first electrode 410, a first charge transport layer 310, a perovskite layer 100, a second charge transport layer 320, and a second electrode 420 stacked together. In the thickness direction (Z direction) of the perovskite layer, the first charge transport layer 310 and the second charge transport layer 320 are respectively disposed on opposite sides of the perovskite layer 100. The first electrode 410 is disposed on the side of the first charge transport layer 310 away from the perovskite layer 100, and the second electrode 420 is disposed on the side of the second charge transport layer 320 away from the perovskite layer 100. In some embodiments, the first electrode is a transparent electrode, and the second electrode is a metal electrode.

[0314] Figure 9 This is a schematic diagram of the structure of an optoelectronic device according to an embodiment of this application. The optoelectronic device 10 includes a substrate layer 500, a first electrode 410, a first charge transport layer 310, a perovskite layer 100, a second charge transport layer 320, and a second electrode 420 stacked together. In the thickness direction (Z direction) of the perovskite layer, the first charge transport layer 310 and the second charge transport layer 320 are respectively disposed on opposite sides of the perovskite layer 100. The first electrode 410 is disposed on the side of the first charge transport layer 310 away from the perovskite layer 100, and the second electrode 420 is disposed on the side of the second charge transport layer 320 away from the perovskite layer 100. The substrate layer 500 is disposed on the side of the first electrode 410 away from the perovskite layer 100. The substrate layer 500 supports the optoelectronic device 10.

[0315] In some embodiments of this application, the optoelectronic device can be a formal structure or an inverse structure.

[0316] In some embodiments of this application, the optoelectronic device is an inverted pin structure or a formal nip structure.

[0317] Figure 10 This is a schematic diagram of the structure of an inverted optoelectronic device according to an embodiment of this application. The optoelectronic device 10 includes a substrate layer 500, an incident light-side electrode 700, a hole transport layer 610, a perovskite layer 100, an electron transport layer 620, and a back electrode 800 stacked together. In the thickness direction (Z direction) of the perovskite layer, the hole transport layer 610 and the electron transport layer 620 are respectively disposed on both sides of the perovskite layer 100. The incident light-side electrode 700 is disposed on the side of the hole transport layer 610 away from the perovskite layer 100, the back electrode 800 is disposed on the side of the electron transport layer 620 away from the perovskite layer 100, and the substrate layer 500 is disposed on the side of the incident light-side electrode 700 away from the perovskite layer 100.

[0318] Figure 11This is a schematic diagram of the structure of an optoelectronic device according to an embodiment of this application. The optoelectronic device 10 includes a substrate layer 500, an incident light-side electrode 700, an electron transport layer 620, a perovskite layer 100, a hole transport layer 610, and a back electrode 800 stacked together. In the thickness direction (Z direction) of the perovskite layer, the hole transport layer 610 and the electron transport layer 620 are respectively disposed on both sides of the perovskite layer 100. The incident light-side electrode 700 is disposed on the side of the electron transport layer 620 away from the perovskite layer 100. The back electrode 800 is disposed on the side of the hole transport layer 610 away from the perovskite layer 100. The substrate layer 500 is disposed on the side of the incident light-side electrode 700 away from the perovskite layer 100.

[0319] It is understood that the hole transport layer includes hole transport materials. Without limitation, the hole transport materials in the hole transport layer may include, but are not limited to, one or more of the following materials and their derivatives: hole transport organic materials and hole transport inorganic materials.

[0320] In some embodiments of this application, the hole transport material includes hole transport organics. Without limitation, the hole transport organics may include, but are not limited to, poly[bis(4-phenyl)(2,4,6-trimethylphenyl)amine] (PTAA), poly(3,4-ethylenedioxythiophene)-polystyrene sulfonic acid, 2,2',7,7'-tetratetra[N,N-di(4-methoxyphenyl)amino]-9,9'-spirobifluorene, poly-3-hexylthiophene, methoxytriphenylamine-fluoroformamidinium, triphenylamine with a triphenylene core, 3,4-ethylenedioxythiophene-methoxytriphenylamine, N-(4-aniline)carbazole-spirobifluorene, polythiophene, carbazole-based monomers or polymers (such as [4-(3,6-dimethoxy-9H-carbazole-9-yl)butyl]phosphonic acid (MeO-4PACz), [4-(3,6-dimethyl-9H-carbazole-9-yl)butyl]phosphonic acid (MeO-4PACz), [4-(3,6-dimethyl-9H-carbazole-9-yl)butyl]phosphonic acid... The hole transport material comprises one or more of the following: [4-(9H-carbazole-9-yl)butyl]phosphonic acid (Me-4PACz), [4-(3,6-dibromo-9H-carbazole-9-yl)butyl]phosphonic acid (Br-4PACz), [2-(3,6-dimethoxy-9H-carbazole-9-yl)ethyl]phosphonic acid (MeO-2PACz), [2-(9H-carbazole-9-yl)ethyl]phosphonic acid (2PACz), [2-(3,6-dibromo-9H-carbazole-9-yl)ethyl]phosphonic acid (Br-2PACz), triphenylamine monomers or polymers, aromatic monomers or polymers, etc. In some embodiments of this application, the hole transport material includes hole transport inorganic substances. Non-limitingly, the hole transport inorganic material may include, but is not limited to, one or more of metal oxides (which may be referred to as the first metal oxide), cuprous iodide and cuprous thiocyanate, molybdenum sulfide, etc.; wherein, the metal oxide in the hole transport material may include, but is not limited to, one or more of nickel oxide, molybdenum oxide, cuprous oxide, vanadium oxide, and tungsten oxide. As a non-limiting example, in the hole transport material, the metal element in the first metal oxide may include one or more of nickel (Ni), molybdenum (Mo), copper (Cu), vanadium (V), and tungsten (W).

[0321] It is understood that the electron transport layer includes electron transport materials. Without limitation, the electron transport materials in the electron transport layer may include, but are not limited to, one or more of the following materials and their derivatives, impurities, and passivated materials: fullerenes and their derivatives, imide compounds, metal oxides, metal sulfides, metal fluorides, cyano-containing polyphenylacetylene, boron-containing polymers, copper bath, red phenanthroline, hydroxyquinoline aluminum, oxadiazole compounds, quinone compounds, etc.; exemplarily, fullerenes and their derivatives include, but are not limited to, [6,6]-phenyl-C 61 methyl butyrate (PC) 61BM), [6,6]-phenyl-C 71 methyl butyrate (PC) 71 BM), Fullerene C 60 Fullerene C 61 Fullerene C 70 The imide compounds include, but are not limited to, one or more of perylene imide materials, naphthalene imide materials, phthalimide, succinimide, N-bromosuccinimide, glutarimide, or maleimide; metal oxides (which may be referred to as second metal oxides), perylene imide materials, naphthalene imide materials, etc. Among these, the metal oxides in the electron transport materials may include one or more of tin oxide, zinc oxide, etc. As a non-limiting example, in the electron transport materials, the metal element in the second metal oxide may include one or more of tin (Sn), magnesium (Mg), indium (In), molybdenum (Mo), titanium (Ti), and zinc (Zn). Metal sulfides include indium sulfide or zinc sulfide; metal fluorides include one or more of lithium fluoride (LiF), sodium fluoride, magnesium fluoride (MgF2), and calcium fluoride (CaF2).

[0322] Without limitation, the metal oxide in the first charge transport layer may refer to a first metal oxide (in which case the first charge transport layer is a hole transport layer) or a second metal oxide (in which case the first charge transport layer is an electron transport layer).

[0323] In some embodiments of this application, the first charge transport layer is a hole transport layer. In this case, in addition to the first metal oxide, the first charge transport layer may also include one or more other types of hole transport materials, as described above.

[0324] In some embodiments of this application, the first charge transport layer is an electron transport layer. In this case, in addition to the second metal oxide, the first charge transport layer may also include one or more other types of electron transport materials, as described above.

[0325] In this application, the terms "first metal oxide" and "second metal oxide" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or quantity, nor should they be construed as implicitly indicating the importance or quantity of the indicated technical features.

[0326] In this application, unless otherwise specified, "perovskite material" refers to a class of semiconductor materials having a crystal structure similar to that of the natural mineral calcium titanate (CaTiO3). Typically, perovskite materials comprise a first cation, a second cation, and an anion. The anion and the second cation together form an octahedral structure, with the anion located at the body center of the octahedron and the second cation located at the six vertices. The first cation fills the voids between the octahedra to achieve charge balance and maintain crystal structure stability. Adjacent octahedral structures are connected by sharing vertices, thus forming a continuous crystal lattice structure. Unless otherwise specified, the first cation may be denoted as A and referred to as an A-site ion or A-site cation; the second cation may be denoted as B and referred to as a B-site ion or B-site cation; and the anion may be denoted as X and referred to as an X-site ion or X-site anion.

[0327] In some embodiments of this application, the first cation is relatively large and the second cation is relatively small.

[0328] In some embodiments of this application, the perovskite tolerance factor is in the range of 0.85 to 1.0. This is advantageous for obtaining a more stable perovskite crystal structure.

[0329] In this application, "perovskite tolerance factor (t)" has a meaning known in the art, and its calculation formula is as follows: , where R A R is the ionic radius of the A-site ion. B R is the ionic radius of the B-site ion. X Let X be the ionic radius of the ion at the X site.

[0330] The first cation in a perovskite material can be an organic cation, an inorganic cation, or a mixture of organic and inorganic cations; it is understood that the first cation in a perovskite material can be one or more types. In some embodiments of this application, the first cation includes a monovalent cation, and more specifically, it can be a monovalent cation.

[0331] The second cation in a perovskite material can be an organic cation, an inorganic cation, or a mixture of organic and inorganic cations; it is understood that the type of the second cation in the perovskite material can be one or more. In some embodiments of this application, the second cation includes a divalent cation, and more specifically, a divalent cation. In some embodiments of this application, the second cation includes a combination of a monovalent cation (denoted as C) and a trivalent cation (denoted as D).

[0332] In some embodiments of this application, the anions in the perovskite material include one or more of halogens and pseudohalogens. "Pseudohalogens," also known as halogen-like substances, refer to atomic groups composed of two or more elements that, as a whole, possess chemical properties similar to halogens. Anionic pseudohalogens may be referred to as pseudohalogen anions. Non-limiting examples of pseudohalogens may include one or more of thiocyano (SCN), oxocyano (OCN), etc. Non-limiting examples of pseudohalogen anions may include SCN. - OCN - CNO - OSCN - SH - CN - SeCN - One or more of the following. It is understood that pseudohalogens present in perovskite materials can act as X-site ions. In some embodiments of this application, the X-site anion is a monovalent anion.

[0333] In some embodiments of this application, the perovskite material includes perovskite-type metal halides.

[0334] Unless otherwise stated in this application, the anions in perovskite materials or perovskite-type metal halides may include one or more of halogen anions and pseudohalogen anions.

[0335] In some embodiments of this application, the anion in the perovskite material or perovskite-type metal halide is selected from one or more of halogen anions and pseudohalogen anions.

[0336] In some embodiments of this application, the perovskite material or perovskite-type metal halide may include at least one of ABX3 and A2CDX6; wherein A is a monovalent cation, B is a divalent cation, X is a monovalent anion, C is a monovalent cation, and D is a trivalent cation.

[0337] Without limitation, in perovskite-type metal halides, A can be a monovalent inorganic cation, a monovalent organic cation, or a mixed cation of monovalent organic and monovalent inorganic cations.

[0338] In some embodiments of this application, in the perovskite material or perovskite-type metal halide, A is a monovalent inorganic cation; optionally, A includes Li. + Na + K + 、Rb + and Cs + One or more of them.

[0339] In some embodiments of this application, in the perovskite material or perovskite-type metal halide, A is a monovalent organic cation. Optionally, A includes at least one of methylamino, ethylamino, propylamino, butylamino, pentamino, hexamino, formamidinyl, and imidazolyl.

[0340] Without limitation, the A in perovskite materials or perovskite-type metal halides may include Cs. + K + 、Rb + Li + One or more of monovalent organic cations, etc.

[0341] Non-limiting examples of monovalent organic cations include (NR) 31 R 32 R 33 R 34 ) + 、(R 31 R 32 N=CR 33 R 34 ) + 、(R 31 R 32 NC(R 35 )=NR 33 R 34 ) + or (R) 31 R 32 NC(NR 35 R 36 )=R 33 R 34 ) + , where R 31 R 32 R 33 R 34 R 35 and R 36 Each is independently selected from H and C. 1-20 Alkyl, aryl, substituted C 1-20 Alkyl or substituted aryl; wherein, C 1-20 Alkyl and substituted C 1-20 The "C" in alkyl 1-20 Each alkyl group can be independently selected as C. 1-15 Alkyl, further optionally C 1-10 Alkyl, and further optionally C 1-8 Alkyl, and further optionally C 1-6 Alkyl, and further optionally C 1-4 Alkyl, and further optionally C 1-3 Alkyl, and further optionally methyl. The "aryl" in aryl and substituted aryl groups can each independently be C10.6-20 Aryl, further optionally C 6-12 Aryl, and further alternatively C 6-10 Aryl, further optionally phenyl or naphthyl, and further optionally phenyl. Substituted C 1-20 In alkyl and substituted aryl groups, each substituent is independently C1. 1-10 Hydrocarbon group, further optionally C 1-6 Alkyl or C 6-10 Aryl, and may further be methyl or phenyl.

[0342] Non-limiting examples of monovalent organic cations include CH3NH3 + (Methylamine, MA) + ), NH2CH=NH2 + (Formamidin, can be written as FA) + ), dimethylamine cation, ethylamine cation, propylamine cation, butylamine cation, pentamine cation, hexamine cation, imidazole cation.

[0343] In some embodiments of this application, in the perovskite-type metal halide, A includes a monovalent organic cation and Cs. + One or more of them.

[0344] In some embodiments of this application, in the perovskite material or perovskite-type metal halide, B includes divalent cations of one or more of the following elements: lead, tin, zinc, titanium, antimony, bismuth, nickel, iron, cobalt, silver, copper, gallium, germanium, magnesium, calcium, indium, aluminum, manganese, chromium, molybdenum, and europium.

[0345] In some embodiments of this application, in the perovskite material or perovskite-type metal halide, C represents a monovalent inorganic cation; optionally, C includes Cs. + Ag + K + and Ru + One or more of them.

[0346] In some embodiments of this application, D represents a trivalent metal cation; optionally, D includes Bi. 3+ Ni 3+ Fe 3+ Sb 3+ In 3+ and Cu 3+ One or more of them, and further optionally, D includes In 3+ Bi 3+ Sb 3+ One or more of them.

[0347] In some embodiments of this application, X represents a halide anion; optionally, X includes F. -Cl - ,Br - and I - One or more of them, and optionally, X includes Cl - ,Br - and I - One or more of them.

[0348] In some embodiments of this application, the perovskite material includes perovskite-type metal halides, and the monovalent cation of the perovskite material includes FA. + and Cs + .

[0349] In some embodiments of this application, the perovskite material includes perovskite-type metal halides, and the monovalent cation of the perovskite material includes FA. + MA + and Cs + .

[0350] In some embodiments of this application, FA + The molar percentage of monovalent cations in perovskite materials is 0.8~1.0.

[0351] In some embodiments of this application, MA + The molar percentage of monovalent cations in perovskite materials is 0 to 1.0.

[0352] In some embodiments of this application, Cs + The molar percentage of monovalent cations in perovskite materials is 0~1.0.

[0353] In some embodiments of this application, the perovskite material includes perovskite-type metal halides, and the divalent cation of the perovskite material includes Pb. 2+ Furthermore, it can be used for Pb 2+ .

[0354] In some embodiments of this application, the perovskite material includes perovskite-type metal halides, and the monovalent anions of the perovskite material include iodide anions and bromide anions.

[0355] In some embodiments of this application, the molar percentage of iodine anions in the monovalent anions of the perovskite material is 0 to 1.0.

[0356] In some embodiments of this application, the molar percentage of bromide anions in the monovalent anions of the perovskite material is 0 to 1.0.

[0357] In this application, unless otherwise specified, the term "aryl" refers to an aromatic hydrocarbon group derived from an aromatic cyclic hydrocarbon compound by losing one hydrogen atom, that is, forming a monovalent linking site directly on the ring. It can be a monocyclic aryl, a fused-ring aryl, or a polycyclic aryl; for polycyclic rings, at least one is an aromatic ring system. For example, "C6- 10 "Aryl" refers to an aryl group containing 6 to 10 carbon atoms. Each time it appears, it can be independently C6 aryl, C8 aryl, C9 aryl, or C6 aryl. 10 Aryl. For example, "C6- 20 "Aryl" refers to an aryl group containing 6 to 20 carbon atoms. Each time it appears, it can be independently, but is not limited to, C6 aryl (such as phenyl), C8 aryl (such as benzocyclobutenyl), C9 aryl (such as indenyl), C6 aryl, C8 aryl, C9 ... 10 Aryl (such as naphthyl), C 12 Aryl (such as acenaphthene, biphenyl), C 13 Aryl (such as fluorene), C 14 Aryl (such as anthracene, phenanthrene), C 18 Aryl (such as phenylene) or C 20 Aryl groups (such as dinaphthalene-based phenyl groups). Examples of suitable aromatic cyclic hydrocarbons that can be derived to form aryl groups include, but are not limited to: benzene, benzocyclobutene, biphenyl, indene, naphthalene, acenaphthene, fluorene, anthracene, phenanthrene, triphenylene, dinaphthalene-based phenyl groups and their derivatives.

[0358] Without limitation, in perovskite-type metal halides, B can be an inorganic cation.

[0359] In some embodiments of this application, in the perovskite-type metal halide, B includes a divalent cation. Optionally, B includes a divalent cation of one or more of the following elements: lead, tin, zinc, titanium, antimony, bismuth, nickel, iron, cobalt, silver, copper, gallium, germanium, magnesium, calcium, indium, aluminum, manganese, chromium, molybdenum, europium, etc.

[0360] Without limitation, B in perovskite-type metal halides may include Pb. 2+ Sn 2+ Fe 2+ Mn 2+ Ni 2+ 、Ge 2+ Co 2+ and Sb 2+ One or more of them.

[0361] In perovskite-type metal halides, X can be an inorganic anion, an organic anion, or a mixture of organic and inorganic anions.

[0362] In some embodiments of this application, in the perovskite-type metal halide, X is a halide anion; optionally, X includes F. - Cl- ,Br - and I - One or more of them, and optionally, X includes Cl - ,Br - and I - One or more of the following. In some embodiments, X in the perovskite metal halide can be I. - ,Br - and Cl - One or more of them.

[0363] Without limitation, X in perovskite-type metal halides may include I. - ,Br - One or two of them. X can be I. - ,Br - Or a combination thereof. In some embodiments, X is I. - .

[0364] Non-limitingly, in perovskite-type metal halides, C can be an inorganic cation, an organic cation, or a mixed organic-inorganic cation. In some embodiments of this application, C is a monovalent inorganic cation; optionally, C includes Cs. + Ag + K + and Ru + One or more of the following. In some embodiments of this application, C can be silver ions (Ag). + ).

[0365] In a non-limiting sense, in perovskite metal halides, D can be an inorganic cation, an organic cation, or a mixed organic-inorganic cation.

[0366] In some embodiments of this application, D is a trivalent metal cation; optionally, D includes Bi. 3+ Ni 3+ Fe 3+ Sb 3+ In 3+ , and Cu 3+ One or more of them, and further optionally, D includes In 3+ Bi 3+ Sb 3+ One or more of these. In some embodiments, D is a bismuth cation (Bi). 3+ ), antimony cation (Sb) 3+ ) and indium cations (In 3+ At least one of the following.

[0367] In some embodiments of this application, the perovskite material accounts for more than or equal to 95% of the mass of the perovskite layer, and can be selected as 95% to 100%.

[0368] Non-limiting, the first electrode and the second electrode may each independently comprise a conductive material. The conductive material in the first electrode and the conductive material in the second electrode may each independently comprise an organic conductive material, an inorganic conductive material, or an organic-inorganic mixed conductive material.

[0369] As an example, organic-inorganic hybrid conductive materials include both organic and inorganic conductive components.

[0370] As a non-limiting example, organic conductive materials may include conductive polymers, wherein non-limiting examples of conductive polymers may include one or more of PEDOT (poly-3,4-ethylenedioxythiophene), polythiophene, polyacetylene, etc.

[0371] As a non-limiting example, inorganic conductive materials may include one or more of transparent conductive oxides, metallic conductive materials, and carbon conductive materials. Non-limiting examples of transparent conductive oxides may include one or more of fluorine-doped tin oxide (FTO), indium tin oxide (ITO), aluminum-doped zinc oxide (AZO), boron-doped zinc oxide (BZO), indium zinc oxide (IZO), tungsten-doped indium oxide (IWO), indium gallium zinc oxide (IGZO), and antimony-doped tin oxide (ATO). Metallic conductive materials may include one or more of gold (Au), silver (Ag), copper (Cu), aluminum (Al), nickel (Ni), chromium (Cr), bismuth (Bi), platinum (Pt), magnesium (Mg), molybdenum (Mo), and tungsten (W).

[0372] In some embodiments of this application, non-limiting examples of inorganic conductive materials include metallic conductive materials. Further, metallic conductive materials may include any one of gold (Au), silver (Ag), copper (Cu), aluminum (Al), nickel (Ni), chromium (Cr), bismuth (Bi), platinum (Pt), magnesium (Mg), or any suitable mixture of the aforementioned elements.

[0373] It is understood that transparent electrodes comprise transparent conductive materials. In some embodiments of this application, the transparent conductive material contained in the transparent electrode may include conductive oxides. Non-limitingly, the conductive oxide in the transparent electrode may include one or more of indium tin oxide, fluorine-doped tin oxide, indium-doped tungsten oxide, indium-doped zinc oxide, and aluminum-doped zinc oxide. In some embodiments of this application, the transparent conductive material in the transparent electrode may be exemplified, but is not limited to, one or more of the following materials: fluorine-doped tin oxide (FTO), indium tin oxide (ITO), aluminum-doped zinc oxide (AZO), boron-doped zinc oxide (BZO), indium zinc oxide (IZO), tungsten-doped indium oxide (IWO), indium gallium zinc oxide (IGZO), and antimony-doped tin oxide (ATO), etc.

[0374] In some embodiments of this application, one of the first electrode and the second electrode is a metal electrode. The metal electrode may include one or more metallic elements selected from gold (Au), silver (Ag), copper (Cu), aluminum (Al), nickel (Ni), chromium (Cr), bismuth (Bi), platinum (Pt), magnesium (Mg), molybdenum (Mo), tungsten (W), etc.

[0375] In some embodiments of this application, the electrode material of the first electrode includes at least one of indium tin oxide (ITO), lanthanide-doped indium oxide, fluorine-doped tin oxide (FTO), antimony-doped tin oxide (ATO), boron-doped zinc oxide (BZO), aluminum-doped zinc oxide (AZO), indium zinc oxide (IZO), gallium zinc oxide (GZO), tungsten-doped indium oxide (IWO), Au, Ag, Cu, Al, Ni, Cr, Bi, Pt, Mg, Mo, W and their alloys, graphite, graphene, and carbon nanotubes; optionally, it includes at least one of Ag, Cu, C, Au, Al, ITO, AZO, BZO or IZO, and further optionally, it includes at least one of Cu, Ag, and Au.

[0376] In some embodiments of this application, the second electrode is a back electrode. The back electrode may include one or more of indium tin oxide (ITO), lanthanide-doped indium oxide, fluorine-doped tin oxide (FTO), antimony-doped tin oxide (ATO), boron-doped zinc oxide (BZO), aluminum-doped zinc oxide (AZO), indium zinc oxide (IZO), gallium zinc oxide (GZO), and tungsten-doped indium oxide (IWO), and the metal may include one or more metallic elements selected from Au, Ag, Cu, Al, Ni, Cr, Bi, Pt, and Mg.

[0377] The substrate layer involved in the embodiments or examples of this application can be, but is not limited to, a rigid substrate layer or a flexible substrate layer. A non-limiting example of a rigid substrate layer is a glass substrate layer. In some embodiments, the rigid substrate layer is transparent glass. In some embodiments, the substrate layer is provided by a transparent conductive oxide film glass (TCO glass), wherein the glass serves as the substrate layer, and the TCO is a transparent conductive oxide film material; non-limiting examples of TCO materials include ITO, FTO, etc.

[0378] In some embodiments of this application, the material of the flexible substrate layer may be, for example, but not limited to, organic polymer materials. Furthermore, it may be composed of one or more of the following materials mixed in different proportions: including but not limited to polyvinyl alcohol (PVA), polyester (PET), polyimide (PI), polyethylene naphthalate (PEN), polydimethylsiloxane (PDMS), etc.

[0379] It is understood that the structure of the optoelectronic device involved in this application is not limited to the structural layers listed above. Other functional layers or interface layers, such as buffer layers and insertion layers, can also be introduced as needed. In some embodiments, the optoelectronic device can be provided with a buffer layer of appropriate energy level, which can play one or more roles such as reducing the energy level barrier, promoting energy level matching, improving carrier extraction efficiency, passivating interface defect states, protecting the light-absorbing layer, inhibiting the oxidation and decomposition of water molecules and oxygen on the battery, improving energy conversion efficiency, and improving device stability. Depending on the location of the buffer layer, the type of buffer layer can include four types: a buffer layer between the hole transport layer and the anode, a buffer layer between the electron transport layer and the cathode, a buffer layer between the hole transport layer and the light-absorbing layer, and a buffer layer between the electron transport layer and the light-absorbing layer. Materials that can be used for buffer layers in optoelectronic devices can include, but are not limited to, Cu2O, NiO, AZO, TiO2, etc. In some embodiments, an insertion layer can be provided between the electron transport layer and the second electrode. This insertion layer is used to block the transport of holes and can also be called a hole blocking layer. Examples of materials for the insertion layer include bath copper phosphate (BCP) and tin oxide.

[0380] In some embodiments of this application, the optoelectronic device 10 includes Figure 12 The structure shown ( Figure 12 The structure shown is a schematic cross-sectional view of the device along its thickness direction. The optoelectronic device 10 includes a substrate layer 500, a first electrode 410, a first transport layer 310, a perovskite layer 100, a second transport layer 320, and a second electrode 420 stacked together. The positional relationship of each structural layer is as follows: Figure 9Similarly, the optoelectronic device 10 is further provided with three types of cross-layer channel regions: a first channel region P1, a second channel region P2, and a third channel region P3. Utilizing the channel group formed by the first channel region P1, the second channel region P2, and the third channel region P3, the solar cell is divided into several series-connected sub-cells. Each sub-cell includes a first channel region P1, a second channel region P2, and a third channel region P3 arranged sequentially, with the second channel region P2 located between the first channel region P1 and the third channel region P3. The first channel region P1, the second channel region P2, and the third channel region P3 can be connected to the structural layers that are spaced apart, thereby connecting the circuit between the first electrode of one sub-cell and the second electrode of the adjacent sub-cell, forming a series structure. The first channel region P1, the second channel region P2, and the third channel region P3 can each be an independent linear channel region, formed by laser etching or a mask. The number of first channel regions P1, second channel regions P2, and third channel regions P3 can each be one or more independently. The number of first channel regions P1, second channel regions P2, and third channel regions P3 corresponds to the number of sub-cells. Without limitation, the first channel regions P1, second channel regions P2, and third channel regions P3 can be configured as follows: the first channel region P1 is used to divide the first electrode 410 to prevent short circuits between adjacent sub-cells; the second channel region P2 is used to penetrate and divide the second charge transport layer 320, the perovskite layer 100, and the first charge transport layer 310, with the interior of the second channel region filled with a conductive material such that both ends of the conductive material are connected to the second electrode 420 and the first electrode 410 respectively. The material of this conductive material can be the same as the material of the second electrode 420 to achieve integral fabrication during the fabrication process of the second electrode 420, or it can be a different material from the second electrode 420; the third channel region P3 is used to penetrate and at least divide the second electrode 420. Figure 12 In the example, the third channel region P3 is used to penetrate and divide the second electrode 420, the second charge transport layer 320, the perovskite layer 100, and the first charge transport layer 310. One end of the third channel region P3 is connected to the surface of the first electrode 410, and the other end extends out of the outer surface of the second electrode 420. The purpose is to isolate the second electrode between two adjacent sub-cells to prevent short circuits. In this way, a series connection between adjacent sub-cells is achieved.

[0381] In some embodiments of this application, Figure 12 The substrate 500 in the structure shown is a light-incident glass substrate.

[0382] In some embodiments of this application, the filling material in the first channel region P1 of the optoelectronic device can be the same as the first charge transport layer, or it can be filled with an insulating material, as long as it can prevent short circuits between adjacent series-connected sub-cells.

[0383] In some embodiments of this application, the filling material in the second channel region P2 of the optoelectronic device may be consistent with the second electrode.

[0384] In some embodiments of this application, the width of the first channel region P1 is 10~50μm, such as 15μm, 30μm, etc.

[0385] In some embodiments of this application, the width of the second channel region P2 is 10~200μm, for example 50μm or 150μm. Further, the interval between the second channel region P2 and the first channel region P1 can be 20~80μm, for example 20μm or 50μm.

[0386] In some embodiments of this application, the width of the third channel region P3 is 10~50μm, such as 15μm, 25μm, etc. Further, the interval between the third channel region P3 and the second channel region P2 can be 20~100μm, such as 50μm.

[0387] In some embodiments of this application, the optoelectronic device includes an encapsulating adhesive layer.

[0388] Encapsulating adhesive layers can be used to protect the stability of optoelectronic devices, for example, by isolating them from water, oxygen, and other corrosive substances.

[0389] In some embodiments of this application, the encapsulating adhesive layer includes one or more of the following: epoxy encapsulating adhesive, silicone encapsulating adhesive, polyurethane encapsulating adhesive, UV-curable encapsulating adhesive, ethylene-vinyl acetate copolymer, polyvinyl butyral, ethylene octene copolymer, polyisobutylene, and polyolefin encapsulating adhesive.

[0390] The encapsulating adhesive layer can be stacked using existing techniques in the field. After the optoelectronic device is fabricated, the encapsulating adhesive layer can be stacked at the final structural layer of the solar cell device. In some embodiments of this application, the final structural layer can be a second electrode. For example, lamination technology can be used to laminate the arranged optoelectronic devices or components including the optoelectronic devices with the encapsulating adhesive film, thereby creating an encapsulating adhesive layer on the side of the second electrode facing away from the light-absorbing layer.

[0391] Unless otherwise stated, the encapsulating film and encapsulating layer in this application are transparent materials.

[0392] In some embodiments of the second aspect of this application, a method for fabricating an optoelectronic device is provided.

[0393] In some embodiments of this application, a method for fabricating an optoelectronic device is provided, which includes the following steps:

[0394] S100: Prepare a perovskite precursor solution; wherein the perovskite precursor solution includes perovskite precursor raw materials and solvent, and the perovskite precursor solution also includes metal iodide additives, the metal iodide additives having a dominant crystal face; optionally, the perovskite precursor solution also includes a regulator.

[0395] S200: The perovskite precursor solution is coated, dried, and laser annealed to form a perovskite layer; wherein, the laser annealing includes annealing at a first temperature and a second temperature, wherein the first temperature is lower than the second temperature.

[0396] In some embodiments, the formed perovskite layer can be referred to the perovskite layer in the optoelectronic device described in the first aspect of this application; exemplaryly, the perovskite layer includes perovskite grains, and at least a portion of the outer surface of the perovskite grains is distributed with metal iodides; in the GIWAXS two-dimensional diffraction pattern of the perovskite layer, the orientation angle between the dominant crystal plane of the metal iodide and the dominant crystal plane of the perovskite grain is small, such as less than or equal to 5°; wherein, the definitions of GIWAXS and dominant crystal planes can be referred to the relevant description in the first aspect of this application;

[0397] In some further embodiments, laser annealing includes annealing at a first temperature and a second temperature, wherein the first temperature is lower than the second temperature.

[0398] In this application, unless otherwise specified, "perovskite precursor solution" is in solution form and is also referred to as perovskite precursor solution.

[0399] In this application, unless otherwise specified, "perovskite precursor raw material" refers to the raw material used to form the perovskite crystal structure, which can provide the basic elements in the perovskite crystal structure.

[0400] In this application, unless otherwise specified, "metal iodide additive" refers to a metal iodide added in addition to the perovskite precursor raw material. Typically, the elemental composition of the perovskite precursor raw material matches the chemical elemental composition of the target perovskite material.

[0401] After coating the perovskite precursor solution, some solvent can be removed by vacuum drying. This solvent removal process helps the perovskite precursor material form a perovskite mesophase film containing some residual solvent. During annealing, through the synergistic effect of laser annealing at the first and second temperatures, the metal iodide components in the perovskite mesophase film can be gradually, efficiently, precisely, and uniformly guided to the outer surface of the perovskite grains. In the laser gradient annealing process, the low-temperature annealing at the first temperature allows for appropriate decomposition of the mesophase, inducing the perovskite mesophase components to slowly pre-crystallize under relatively high residual solvent content, and utilizing the residual solvent to uniformly and slowly distribute the metal iodides to the perovskite grain boundaries. The high-temperature annealing at the second temperature, under the induction of the metal iodides with dominant orientation, allows the perovskite components to form high-quality crystals with highly consistent dominant orientation crystal faces, ultimately uniformly positioning the dominant orientation metal iodides on the outer surface of the perovskite grains. It is understood that this is not intended to be limited to the aforementioned theory.

[0402] Furthermore, in the presence of a regulator, the regulator can penetrate the interlayer of the layered structure of the perovskite precursor material (such as BX2), thereby expanding the interlayer spacing of the BX2 crystal structure. A larger interlayer spacing allows organic amine salts such as FA in the precursor solution to more easily enter the BX2 structure, thus enabling the perovskite to grow along the dominant orientation of BX2 during subsequent annealing steps, crystal growth, and fusion, thereby controlling the crystallization quality of the perovskite grains.

[0403] In some embodiments of this application, a method for fabricating an optoelectronic device is provided, which includes the following steps:

[0404] S100: Prepare a perovskite precursor solution; wherein the perovskite precursor solution includes perovskite precursor raw materials and solvent, and the perovskite precursor solution also includes metal iodide additives, the metal iodide additives having a dominant crystal face; optionally, the perovskite precursor solution also includes a regulator.

[0405] S210: Coating and drying the perovskite precursor solution to form a perovskite intermediate phase film layer;

[0406] S220: Laser annealing of the perovskite mesophase film layer to form a perovskite layer; wherein, laser annealing includes annealing at a first temperature and a second temperature, wherein the first temperature is lower than the second temperature.

[0407] In some embodiments of this application, the perovskite mesophase film is a wet film, meaning that some solvent remains. The residual solvent content can be 10%-20%.

[0408] In some embodiments of this application, the target perovskite material includes divalent metal cations. Further, the concentration of the divalent metal cations in the perovskite precursor solution can be 0.5 mol / L to 3 mol / L, optionally 1 mol / L to 2 mol / L, or any of the following concentrations or a range selected from any two of the following concentrations: 0.5 mol / L, 0.6 mol / L, 0.8 mol / L, 0.9 mol / L, 1 mol / L, 1.2 mol / L, 1.4 mol / L, 1.5 mol / L, 1.6 mol / L, 1.8 mol / L, 2 mol / L, 2.2 mol / L, 2.4 mol / L, 2.5 mol / L, 3 mol / L, etc.

[0409] In this application, the "mass percentage of solvent residue after vacuum drying" can be confirmed by the following method: TOF-SIMS analysis is performed on the perovskite mesophase film layer after vacuum drying (VCD) treatment, and the solvent molecule signal intensity (I1) at different depths is monitored. This signal intensity (I0) is then compared with the signal intensity in the coated perovskite mesophase film layer before VCD treatment to obtain the solvent mass M1 in the VCD-treated sample and the solvent mass M0 in the coated sample before VCD treatment, thereby obtaining the residual solvent percentage F in the perovskite mesophase film layer. S =M1 / M0×100%.

[0410] It is understandable that the temperature for laser annealing is higher than or equal to the crystallization temperature of perovskite.

[0411] Unless otherwise stated in this application, "perovskite crystallization temperature" refers to the initial crystallization temperature of perovskite, which is the lowest temperature at which the perovskite precursor begins to undergo a phase transition and transform into perovskite crystals.

[0412] The amount of regulator can be adjusted according to the orientation angle between the dominant crystal plane of the metal iodide and the dominant crystal plane of the perovskite grain in the perovskite layer of the target optoelectronic device, as well as the content of the metal iodide.

[0413] In some embodiments of this application, the solvent for the perovskite precursor solution may include one or more of dimethylformamide (DMF), dimethyl sulfoxide (DMSO), and N-methylpyrrolidone (NMP).

[0414] In some embodiments of this application, the solvent for the perovskite precursor solution can be a mixture of dimethylformamide (DMF) and dimethyl sulfoxide (DMSO). In some embodiments, the volume ratio of DMF to DMSO is 2 to 6, and exemplary volume ratios can be 2, 2.5, 3, 3.5, 4, 4.5, 5, 5.5, 6, etc., but are not limited thereto.

[0415] This method can be used to prepare the optoelectronic devices described in the first aspect of this application.

[0416] In some embodiments of this application, laser annealing employs nanosecond-level pulsed lasers.

[0417] In some embodiments of this application, the laser annealing uses a blue laser with a wavelength of 400nm~500nm; the perovskite component and intermediates have a relatively high absorption rate of blue light, which is more conducive to controlling large-area uniform annealing.

[0418] In some embodiments of this application, the method for fabricating the optoelectronic device satisfies one or more of the following features:

[0419] (b1) The vacuum drying is carried out at a temperature of 20°C to 30°C, a pressure of 80 Pa to 150 Pa, and a duration of 15 to 25 seconds.

[0420] Optionally, after vacuum drying, the mass percentage of the solvent residue is 10% to 20%, or it can be any of the following percentages or a range selected from any two of the following percentages: 10%, 12%, 14%, 15%, 16%, 18%, 20%, etc., based on the initial solvent content before vacuum drying.

[0421] (b2) The regulator includes diC 2-6 Alkylamine hydrochloride and diC 2-6 One or more of alkylamine thiocyanates;

[0422] Optionally, the modifier includes one or more of dipropylamine hydrochloride, dibutylamine hydrochloride, diethylamine thiocyanate, dipropylamine thiocyanate, and dibutylamine thiocyanate;

[0423] The aforementioned types of regulators are beneficial for better exerting the aforementioned effects;

[0424] (b3) The molar percentage of the regulator relative to the perovskite precursor raw material is 0 to 3.5%, which can be selected from 0.45% to 3.5%, or can be any of the following percentages or a range selected from any two of the following percentages: 0.1%, 0.2%, 0.3%, 0.4%, 0.5%, 0.6%, 0.7%, 0.8%, 0.9%, 1%, 1.1%, 1.2%, 1.4%, 1.5%, 1.6%, 1.8%, 2%, 2.2%, 2.4%, 2.5%, 2.6%, 2.8%, 3%, 3.2%, 3.4%, 3.5%, etc.; at this time, it is beneficial to better control the dominant orientation of metal iodides and the orientation angle of the dominant crystal planes of metal iodides on the outer surface of perovskite grains during the crystallization process, and it is also beneficial to achieve higher crystal quality at the same time.

[0425] (b4) The first temperature is 85℃~95℃, and the second temperature is 95℃~105℃;

[0426] Optionally, the laser annealing time at the first temperature is shorter than the laser annealing time at the second temperature;

[0427] Optionally, the laser annealing time at the first temperature is 1s to 5s, and the laser annealing time at the second temperature is 5s to 15s.

[0428] (b5) The laser power for laser annealing at the first temperature is 100W~200W, and the laser power for laser annealing at the second temperature is 550W~650W.

[0429] In some embodiments of this application, laser annealing at a first temperature and laser annealing at a second temperature are performed independently using a constant temperature mode and can be performed independently on a heating platform.

[0430] In some embodiments of this application, the resulting optoelectronic devices are as described in the first aspect of this application.

[0431] In some embodiments of this application, the amount of metal iodide additive added is 0.01% to 3.5% of the mass percentage of the perovskite precursor raw material, and may also be any of the following percentages or a range selected from any two of the following percentages: 0.01%, 0.05%, 0.06%, 0.08%, 0.1%, 0.2%, 0.3%, 0.4%, 0.5%, 0.6%, 0.7%, 0.8%, 0.9%, 1%, 1.1%, 1.2%, 1.4%, 1.5%, 1.6%, 1.8%, 2%, 2.2%, 2.4%, 2.5%, 2.6%, 2.8%, 3%, 3.2%, 3.4%, 3.5%. In some embodiments, when the metal iodide is lead iodide, the amount of lead iodide added relative to the mass percentage of the perovskite precursor raw material can be 0.01% to 3.5%, optionally 0.6% to 3.1%, or can be any of the following percentages or a range selected from any two of the following percentages: 0.01%, 0.05%, 0.06%, 0.08%, 0.1%, 0.2%, 0.3%, 0.4%, 0.5%, 0.6%, 0.7%, 0.8%, 0.9%, 1%, 1.1%, 1.2%, 1.4%, 1.5%, 1.6%, 1.8%, 2%, 2.2%, 2.4%, 2.5%, 2.6%, 2.8%, 3%, 3.2%, 3.4%, 3.5%; when the metal iodide is tin iodide, the amount of tin iodide added relative to the mass percentage of the perovskite material can be 0.45% to 3.5%, or can be any of the following percentages. Alternatively, the percentage can be selected from any two of the following ranges: 0.45%, 0.5%, 0.6%, 0.7%, 0.8%, 0.9%, 1%, 1.1%, 1.2%, 1.4%, 1.5%, 1.6%, 1.8%, 2%, 2.2%, 2.4%, 2.5%, 2.6%, 2.8%, 3%, 3.2%, 3.4%, 3.5%. When the metal iodide is chromium iodide, the amount of chromium iodide added relative to the mass percentage of the perovskite material can be 0.45% to 3.5%, or it can be any one of the following percentages or selected from any two of the following ranges: 0.45%, 0.5%, 0.6%, 0.7%, 0.8%, 0.9%, 1%, 1.1%, 1.2%, 1.4%, 1.5%, 1.6%, 1.8%, 2%, 2.2%, 2.4%, 2.5%, 2.6%, 2.8%, 3%, 3.2%, 3.4%, 3.5%.

[0432] In optoelectronic devices, structural layers other than the perovskite layer can be prepared using one or more of the following methods, including but not limited to: chemical bath deposition, electrochemical deposition, chemical vapor deposition, thermal evaporation, atomic layer deposition, magnetron sputtering, precursor liquid spin coating, precursor liquid slot coating, precursor liquid blade coating, and mechanical pressing. Appropriate methods can be selected to stack the structural layers with adjacent structural layers based on the material properties of each layer. In some embodiments of this application, structural layers in a solar cell can be prepared using one or more of the following methods, including but not limited to: thermal evaporation, precursor liquid coating, etc., wherein the precursor liquid coating method can be precursor liquid spin coating, precursor liquid blade coating, precursor liquid spraying, etc.

[0433] The preparation method provided in the second aspect of this application can be used to prepare the optoelectronic devices described in the first aspect of this application.

[0434] In some embodiments of this application, the method for fabricating the optoelectronic device includes the following steps:

[0435] S10: Perform P1 etching on the first electrode: Perform P1 etching on the first electrode stacked on the substrate layer to form a P1 etching line, exposing the substrate layer to obtain the first substrate, which is then cleaned for later use. The first electrode can be a transparent electrode. The location of the formed P1 etching line can be found in [reference needed]. Figure 12 .

[0436] S20: A first charge transport layer is formed on the first electrode. The first charge transport layer may be a hole transport layer.

[0437] S30: A perovskite layer is formed on the first charge transport layer. See the context for information on the fabrication methods of optoelectronic devices.

[0438] S40: Form a second charge transport layer on the perovskite layer. If the first charge transport layer is a hole transport layer, the second charge transport layer is an electron transport layer. Perform P2 etching to the surface of the first electrode near the hole transport layer. (See reference...) Figure 12 .

[0439] S50: Form a second electrode on the second charge transport layer, perform P3 etching, and etch to the surface of the first electrode near the hole transport layer, then clean the edges. The location of the formed P3 etching line can be found in [reference needed]. Figure 12 .

[0440] In some embodiments of the third aspect of this application, an electrical device is provided, which includes at least one of the optoelectronic devices described in the first aspect of this application and optoelectronic devices prepared by the preparation method of the optoelectronic devices described in the second aspect of this application.

[0441] In some embodiments of the fourth aspect of this application, a power generation device is provided, which includes at least one of the optoelectronic devices described in the first aspect of this application and optoelectronic devices prepared by the preparation method of the optoelectronic devices described in the second aspect of this application.

[0442] Solar cells, multi-junction solar cells, electrical devices, and power generation devices, including the aforementioned optoelectronic devices, can all leverage the advantages of optoelectronic devices.

[0443] In some embodiments, the aforementioned optoelectronic devices or optoelectronic components can be power generation devices or power generation apparatuses that function as electrical devices. The type of power generation device or power generation apparatus may include, but is not limited to, integrated power generation. The location of the power generation device or power generation apparatus may include, but is not limited to, the roof or back panel of a vehicle.

[0444] Furthermore, the aforementioned electrical devices may include mobile devices, such as mobile phones and laptops, electric vehicles, electric trains, ships and satellites, power generation systems, etc., but are not limited to these.

[0445] Figure 14 This is an example of an electrical device. The electrical device 6 is a car, and can further be a pure electric vehicle, a hybrid electric vehicle, or a plug-in hybrid electric vehicle, etc.

[0446] Another example of an electrical device could be a mobile phone, tablet, laptop, calculator, etc.

[0447] Another example of an electrical device could be a wearable device, such as a watch.

[0448] Non-limiting examples of light-emitting devices may include light-emitting diodes (LEDs), laser diodes (LDs), etc. Applications of power-generating devices may include, but are not limited to, lighting and display applications.

[0449] In some embodiments, the aforementioned optoelectronic devices or optoelectronic components can be used as light-emitting devices in a display device. Non-limiting examples of display devices include displays, photodetectors, etc.

[0450] The following describes some embodiments of this application. The embodiments described below are exemplary and are only used to explain this application, and should not be construed as limiting this application. Where the technology or conditions are not specified in the embodiments, they are performed according to the description above, or according to the technology or conditions described in the literature in this field, or according to the product instructions. Reagents or instruments whose manufacturers are not specified are all conventional products that can be obtained commercially, or can be synthesized from commercially available products using conventional methods.

[0451] In the following examples, unless otherwise specified, room temperature refers to 20°C to 30°C.

[0452] In the following examples, the inversion structure is used as a non-limiting example of an optoelectronic device. It is understood that it can also be set as a formal structure. In the test method section, a photovoltaic device is used as an example of performance testing for optoelectronic devices; it is understood that optoelectronic devices can be tested in accordance with the relevant tests for light-emitting devices.

[0453] For test results where specific test methods are not specified below, please refer to the description above.

[0454] Hole transport materials: PTAA (poly(4-phenyl)(2,4,6-trimethylphenyl)amine); FAI (formamidine iodocarbamate) (CAS No.: 879643-71-7); MABr (methylamine bromide) (CAS No.: 6876-37-5); MACl (methylamine chloride) (CAS No.: 593-51-1); PC 61 BM is [6,6]-phenyl-C61-butyrate methyl ester; BCP is 2,9-dimethyl-4,7-diphenyl-1,10-phenanthroline (bath copper).

[0455] I. Fabrication of optoelectronic devices (which can be used as photovoltaic devices for fabricating solar cells)

[0456] Example 1.

[0457] Step S1: Take a set of fluorine-doped tin oxide substrates (FTO conductive glass, first electrode / glass substrate) with dimensions of 300mm × 300mm. Use an infrared laser to etch P1, with a width of approximately 15μm, dividing the entire glass into 44 sub-cells. The series resistance of different sub-cells is greater than 10MΩ. The top and bottom 10mm areas are designated as the component welding area. Clean the etched conductive glass surface: ultrasonically clean with deionized water, acetone, ethanol, and isopropanol for 15 minutes each, then place it in a 70℃ drying oven for 120 minutes to remove residual organic impurities, obtaining a clean and dry substrate material. Then, treat it with ultraviolet-ozone for 15 minutes and transfer it to a nitrogen-filled glove box. The thickness of the first electrode is 500nm.

[0458] Step S2, preparation of the hole transport layer: PTAA is used as the hole transport material. PTAA is dissolved in toluene to form a 2 mg / mL solution. This solution is coated onto an FTO substrate and then annealed at 100°C for 10 min to obtain a thin and flat hole transport layer (approximately 20 nm thick). The hole transport layer is used to extract photogenerated holes and block electrons.

[0459] Step S3, Preparation of the perovskite layer:

[0460] Step S3-1: Dissolve PbI2, FAI, PbBr2, MABr, CsI, and MACl (MACl with a molar percentage of 20 mol% relative to Pb, used as an additive) in a mixed solvent of dimethylformamide (DMF) and dimethyl sulfoxide (DMSO) at a volume ratio of 5.5:1, according to CsI... 0.05 (FA 0.92 MA 0.08 ) 0.95 Pb(I 0.92 Br 0.08 A 1.4 mol / L perovskite precursor base solution was prepared by mixing the elements in the chemical formulas at a molar ratio of 3, followed by the addition of a solution relative to Cs. 0.05 (FA 0.92 MA 0.08 ) 0.95 Pb(I 0.92 Br 0.08 1.5 wt% lead iodide (PbI2) of 3 was added as a metal iodide additive to the above precursor base solution and stirred overnight in a glove box filled with nitrogen to obtain a perovskite precursor solution. The dominant crystal plane of PbI2 is the (100) crystal plane.

[0461] Step S3-2: Using the slit coating method, the perovskite precursor liquid obtained in step S3-1 is filtered using a polytetrafluoroethylene filter head. The filtered precursor liquid is then coated onto the hole transport layer. Part of the solvent in the perovskite precursor liquid is dried under vacuum (vacuum drying pressure is 100 Pa, temperature is 30 °C, and drying time is 20 s) to obtain a perovskite intermediate phase film layer containing residual solvent (or referred to as a perovskite precursor film).

[0462] In step S3-3, the perovskite mesophase film layer obtained by coating is subjected to laser gradient annealing process. Based on nanosecond pulsed laser, a 450nm blue laser with a power of 150W is used. The stage temperature is set to 90°C. The laser spot (300mm×300mm) is used to irradiate the entire perovskite wet film for 2s. Then the power is increased to 600W and the temperature is maintained at 100°C for 10s to form a perovskite thin film (i.e., perovskite layer) with a thickness of about 440nm.

[0463] Step S4, Fabrication of the electron transport layer: PC 61 BM was dissolved in chlorobenzene at 20 mg / mL, coated onto the perovskite layer, and then annealed on a heating stage at 70°C for 10 minutes to form an electron transport layer with a thickness of approximately 60 nm.

[0464] Step S5, preparation of the interface layer (insertion layer): Dissolve BCP in methanol to form a 0.5 mg / mL solution, coat it on the electron transport layer, and then anneal it on a heating stage at 70°C for 10 minutes to form an interface layer with a thickness of about 5 nm.

[0465] P2 is laser-etched, with a width of 50 μm and a depth reaching the FTO layer. The spacing between P2 and P1 is 50 μm.

[0466] Step S6, fabrication of the back electrode (second electrode): Using a vacuum thermal evaporation deposition apparatus, a 100 nm thick copper electrode is deposited on the interface layer prepared in step S5 at a speed of 0.5~2 Å / s. P3 is laser etched, with a width of 25 μm and a depth reaching the FTO layer. The spacing between P3 and P2 is 50 μm (the etch lines are positioned sequentially as P1 / P2 / P3). Then, infrared edge cleaning is used on the assembly. The optoelectronic device is thus fabricated.

[0467] The prepared optoelectronic devices can be used as photovoltaic devices for device performance testing.

[0468] Examples 2-5 employ essentially the same method as Example 1 to prepare optoelectronic devices including a perovskite layer, the difference being the addition of a modifier in step S-1 and / or adjustment of the mass percentage of the modifier relative to the metal iodide additive; the remaining steps are the same as in Example 1. In the prepared optoelectronic devices, the dominant crystal plane of the metal iodide and the dominant crystal plane of the perovskite grains form different orientation angles α1. See Table 1 for details.

[0469] Example 6 uses essentially the same method as Example 4 to prepare an optoelectronic device including a perovskite layer. The difference is that the PbI2 with the (100) crystal plane predominant orientation in step S3-1 is replaced with PbI2 with the (111) crystal plane predominant orientation. The remaining operation steps are the same as in Example 4. See Table 1 for details.

[0470] Examples 7-9 employ essentially the same method as Example 4 to prepare optoelectronic devices including a perovskite layer, the difference being the change in the amount of lead iodide (as a metal iodide additive) used in step S-1; the remaining steps are the same as in Example 4. See Table 1 for details.

[0471] Example 10 uses essentially the same method as Example 4 to prepare an optoelectronic device including a perovskite layer, the difference being that the perovskite precursor material in step S3-1 is replaced with FA. 0.95 Cs 0.05 The elemental molar ratio of the PbI3 chemical formula is the same as in Example 4, and the remaining operating steps are the same. See Table 1 for details.

[0472] Example 11 uses essentially the same method as Example 4 to prepare an optoelectronic device including a perovskite layer. The difference is that the vacuum drying conditions in step S3-2 are: a vacuum drying pressure of 150 Pa, a temperature of 20 °C, and a drying time of 15 s, thereby changing the solvent residue in the perovskite intermediate phase film. The remaining operation steps are the same as in Example 4. See Table 1 for details.

[0473] Example 12 uses essentially the same method as Example 4 to fabricate an optoelectronic device including a perovskite layer. The difference lies in the laser annealing conditions in step S3-3: a 450nm blue laser with a power of 200W is used, based on a nanosecond pulsed laser. The stage temperature is set to 90°C, and the laser spot irradiates the entire perovskite wet film for 4 seconds. Subsequently, the power is increased to 550W and held at 105°C for 10 seconds. The remaining operation steps are the same as in Example 4. See Table 1 for details.

[0474] Comparative Example 1 uses the same method as Example 4 to prepare an optoelectronic device including a perovskite layer. The difference is that the laser gradient annealing process in step S3-3 is replaced with a single-temperature hot plate annealing process (conventional annealing process) with parameters of 135°C for 10 min. The remaining operation steps are the same as in Example 4.

[0475] Comparative Example 2. A photoelectric device comprising a perovskite layer was prepared using essentially the same method as in Example 4, except that the vacuum drying conditions in step S3-2 were changed to: a vacuum drying pressure of 100 Pa, a temperature of 30 °C, and a drying time of 60 s, thereby altering the solvent residue in the perovskite intermediate phase film. The remaining operation steps were the same as in Example 4. See Table 1 for details.

[0476] Comparative Example 3 fabricated an optoelectronic device including a perovskite layer using essentially the same method as Example 4, except that the laser annealing conditions in step S3-3 were single-power annealing: based on a nanosecond pulsed laser, a 450nm blue laser was used with a power of 600W, the stage temperature was set to 100°C, and the laser spot irradiated the entire perovskite wet film for 12s. The remaining operation steps were the same as in Example 4. See Table 1 for details.

[0477] II. Testing Methods

[0478] (a) Structural Inspection

[0479] 1. GIWAXS test:

[0480] (1) Preparation of perovskite thin film samples: In a low humidity (relative humidity less than 2%) or inert gas environment, the perovskite optoelectronic device is etched open with a diamond glass cutter. At this time, the backplate glass, along with the adhesive film and the second electrode, is separated from the perovskite layer. The side with the perovskite layer is picked up with tweezers. Using a pipette or dropper, a small amount of chlorobenzene and o-xylene solvent is brought into partial and brief contact with the exposed perovskite layer. The surface of the perovskite layer is repeatedly rinsed to remove the electron transport layer material on the surface of the perovskite layer, resulting in the bare perovskite layer. The sample is fixed on the sample stage with conductive adhesive and placed in a vacuum chamber.

[0481] (2) Based on the GIWAXS beamline of the Shanghai Synchrotron Radiation Facility. It features a 5.5-micron monochromatic light detector to resolve minute lattice variations in perovskite thin films, and a white light detector to support rapid scanning. For perovskite thin film samples, the grazing incidence angle was set to 0.2°~0.5° (close to the critical angle for total internal reflection) to enhance surface sensitivity; the X-ray wavelength was selected as 0.1-0.2 nm (tunable at the synchrotron radiation source). A two-dimensional detector was used to record diffraction spots and analyze the (hkl) crystal plane distribution; the orientation factor (e.g., ...) was calculated using the Debye-Scherrer ring integral intensity. <100> (Face preference orientation degree).

[0482] 2. XRD test:

[0483] (1) Prepare perovskite thin film samples in the same way as GIWAXS sample preparation;

[0484] (2) The XRD testing equipment was a Bruker D8 Advance. The XRD parameters were as follows: the X-ray source was Cu Kα1 (wavelength 1.54056 Å), the scanning range (2θ) was 0~80°, and the incident angle (2θ) range was 2°~90°. The X-ray diffractometer was started to begin the measurement. The X-rays passed through the sample, interacted with the crystal, and produced diffracted light, which was then received and recorded by the detector to obtain the XRD data of the perovskite layer. First, the background was subtracted by linear or polynomial fitting, and then the target peaks were marked with ranges.

[0485] The perovskite layer was fixed to the sample stage with conductive adhesive and placed in the vacuum chamber.

[0486] The XRD testing equipment is a Bruker D8 Advance. The XRD testing steps are as follows:

[0487] (1) Preparation of perovskite thin film samples: In a low humidity (relative humidity less than 2%) or inert gas environment, the perovskite optoelectronic device is cut open with a diamond glass cutter. At this time, the backplate glass, along with the adhesive film and the second electrode, is separated from the perovskite layer. The side with the perovskite layer is picked up with tweezers. Using a pipette or dropper, a small amount of chlorobenzene and o-xylene solvent is brought into partial and brief contact with the exposed perovskite layer. The surface of the perovskite layer is repeatedly rinsed to remove the electron transport layer material on the surface of the perovskite layer, resulting in the bare perovskite layer. The bare perovskite layer is then fixed to the sample stage with conductive adhesive and placed in a vacuum chamber.

[0488] (2) Start the X-ray diffractometer and begin the measurement. X-rays pass through the sample, interact with the crystal, and generate diffracted light, which is then received and recorded by the detector to obtain the XRD data of the perovskite layer. First, the background is subtracted by linear or polynomial fitting, and then the target peaks are marked with ranges. The software is used to obtain the full width at half maximum (FWHM) and integral area of ​​the diffraction peaks corresponding to the (100) and (111) crystal planes. The average thickness of different crystal planes in the normal direction is obtained by using the Scherrer formula D=Kλ / (βcosθ).

[0489] 3. TEM test

[0490] High-resolution transmission electron microscopy (HRTEM).

[0491] (III) Device Performance Testing

[0492] 1. Initial performance of the device (optoelectronic devices used in solar cells)

[0493] Under normal temperature and pressure (25℃, 1 atmosphere), a standard light source with AM1.5G was used to simulate sunlight, conforming to the national standard IEC61215. The light intensity was corrected using crystalline silicon solar cells to achieve the intensity of one solar cell. The current-voltage characteristic curve (i.e., current-voltage curve) of the solar cell under the illumination of the light source was measured using a four-channel digital source meter (Keithley 2440). The open-circuit voltage (Voc), short-circuit current density (Jsc), fill factor (FF), and photoelectric conversion efficiency (PCE) of the solar cell were obtained.

[0494] The photoelectric conversion efficiency (PCE) is calculated as follows:

[0495] PCE = Pout / Pin

[0496] = Voc×Jsc×[(Vmpp×Jmpp) / (Voc×Jsc)] / Pin

[0497] = Voc×Jsc×FF / Pin

[0498] Wherein, Pout, Pin, Voc, Jsc, Vmpp, Jmpp, and FF represent the battery's operating output power, incident light power, open-circuit voltage, short-circuit current, maximum power point voltage, maximum power point current, and fill factor, respectively. The incident light power is 100 mW / cm². 2 .

[0499] 2. Device stability determination (aging test)

[0500] After the initial performance test of the device is completed, the cell under test is placed in an atmospheric environment (relative humidity of 65%-85%, ambient temperature of about 15℃-40℃) and left in the dark for 1000 hours. The energy conversion efficiency is then tested again (each test continues until there is no hysteresis in the forward and reverse scans, and the photoelectric conversion efficiency is recorded). The ratio of the photoelectric conversion efficiency after 1000 hours of atmospheric placement to the initial efficiency is calculated and used as the normalized efficiency of the solar cell after 1000 hours of placement, which can be denoted as "1000h retention rate".

[0501] 1000h retention rate = retest efficiency / initial efficiency × 100%. The higher the initial normalized efficiency, the better the device stability.

[0502] III. Test Result Analysis

[0503] According to TEM test results, the optoelectronic devices prepared in Examples 1-12 all exhibit perovskite grains with metal iodide distributed on their outer surfaces, i.e., all contain perovskite grains. Furthermore, α1 (the orientation angle between the dominant crystal plane of the metal iodide and the dominant crystal plane of the perovskite grain in the GIWAXS two-dimensional diffraction pattern of the perovskite layer) is small, satisfying ≤5°. Compared to Comparative Examples 1-3, the prepared optoelectronic devices simultaneously demonstrate improved device stability and enhanced photoelectric conversion efficiency. See Table 2 for details.

[0504] Comparative Example 1 uses conventional annealing (hot plate annealing) instead of laser gradient annealing, resulting in a very large α1.

[0505] The vacuum drying step in Comparative Example 2 increased the temperature and extended the drying time, resulting in less solvent residue in the perovskite mesophase film layer. Compared with Example 4, α1 in Comparative Example 2 was significantly increased.

[0506] Comparative Example 3 was adjusted to single-power laser annealing, and α1 in Comparative Example 3 was significantly increased compared to Example 4.

[0507] Based on the XRD and GIWAXS test results of the perovskite layer, the dominant crystal planes of the metal iodides in the perovskite layer and the dominant crystal planes of the perovskite grains within the GIWAXS test depth can be identified, as shown in Table 1. Exemplary results can be found in the XRD diffraction pattern and GIWAXS diffraction pattern of the perovskite layer in Example 4 (see Table 1). Figure 13 In the XRD diffraction pattern of the perovskite layer in Example 4, the dominant orientation crystal plane of the perovskite grains was found to be the (100) crystal plane, which is the same as the dominant orientation crystal plane of the perovskite grains in Comparative Example 1. In the GIWAXS diffraction pattern of the perovskite layer in Example 4, diffraction signals of both perovskite grains and lead iodide can be observed simultaneously, confirming that the dominant orientation crystal plane of both lead iodide and perovskite grains is the (100) crystal plane, which is the same as the dominant orientation crystal plane of the metal iodide solid precursor. See also Table 2.

[0508] Based on exemplary TEM test results, the thickness of the metal iodide on the outer surface of the perovskite grains in Examples 1-6 can be observed to be within the following range: 20 Å to 50 Å. See Table 2.

[0509] Based on exemplary TEM test results, in Examples 1-6, metal iodides are present at the grain boundaries of perovskite grains, and the content of metal iodides at the grain boundaries of perovskite grains is higher than the sum of the contents on the first and second surfaces of the perovskite layer. See Table 2.

[0510] In the perovskite layer of the optoelectronic devices in Examples 1-11, the proportion of the first perovskite grain relative to the total number of perovskite grains in the perovskite layer is relatively high. See Table 2 for details.

[0511] In Examples 1-11, the dominant crystal faces of the metal iodide are the same as those of the perovskite grains.

[0512] Table 1.

[0513]

[0514] In Table 1, "the amount of lead iodide added as a metal iodide additive" refers to the percentage of the total mass of the perovskite precursor material in the perovskite precursor base solution (excluding additives).

[0515] Table 2.

[0516]

[0517] In Table 2, "first perovskite grain" refers to a perovskite grain with lead iodide distributed on its outer surface.

[0518] In Table 2, α1 is the orientation angle between the dominant crystal plane of the metal iodide and the dominant crystal plane of the perovskite grain in the GIWAXS two-dimensional diffraction pattern of the perovskite layer, as defined above.

[0519] In Table 2, R1 is the ratio of the peak area of ​​the dominant crystal plane of the metal iodide to that of the dominant crystal plane of the perovskite grain, as defined above.

[0520] In Table 2, the “thickness” of metal iodides in the perovskite layer refers to the distribution of metal iodides of the thickness shown in Table 2 on at least a portion of the outer surface of the perovskite grains.

[0521] In Table 2, "higher grain boundary content" means that the distribution content of metal iodide at the grain boundaries of perovskite grains is higher than the sum of the distribution content on the first and second surfaces of the perovskite layer.

[0522] The descriptions of the various implementation methods and embodiments above tend to emphasize the differences between them. Similarities or resemblances can be referenced interchangeably, and for the sake of brevity, they will not be repeated here. The technical features of the implementation methods and embodiments described above can be combined arbitrarily. For the sake of brevity, not all possible combinations of the technical features in the above embodiments have been described. However, as long as the combinations of these technical features do not contradict each other, they should be considered within the scope of this specification.

[0523] It should be noted that this application is not limited to the above-described embodiments and examples. The above-described embodiments and examples are merely examples, and any embodiments and examples that have the same structure and achieve the same effect as the technical concept within the scope of this application are included in the technical scope of this application. The embodiments and examples described above only illustrate several embodiments and examples of this application, and although the descriptions are relatively detailed, they should not be construed as limiting the scope of the patent. Furthermore, various modifications that can be conceived by those skilled in the art to the embodiments or examples, and other ways of constructing embodiments or examples by combining some of the constituent elements of the embodiments or examples, are also included in the scope of this application without departing from the spirit of this application.

Claims

1. An optoelectronic device, characterized in that, Includes a perovskite layer; the perovskite layer includes perovskite grains, and at least a portion of the outer surface of the perovskite grains is distributed with metal iodides. In the GIWAXS two-dimensional diffraction pattern of the perovskite layer, the orientation angle between the dominant crystal plane of the metal iodide and the dominant crystal plane of the perovskite grain is less than or equal to 5°; where GIWAXS refers to grazing wide-angle X-ray scattering; the dominant crystal plane refers to the crystal plane corresponding to the strongest diffraction signal of the corresponding phase in the GIWAXS two-dimensional diffraction pattern.

2. The optoelectronic device according to claim 1, characterized in that, In the GIWAXS two-dimensional diffraction pattern of the perovskite layer, the orientation angle between the dominant crystal plane of the metal iodide and the dominant crystal plane of the perovskite grain is less than or equal to 3°.

3. The optoelectronic device according to claim 1 or 2, characterized in that, The dominant crystal planes of the metal iodide are the same as the dominant crystal planes of the perovskite grains.

4. The optoelectronic device according to claim 3, characterized in that, The dominant crystal plane of the metal iodide and the dominant crystal plane of the perovskite grain are either (100) or (111).

5. The optoelectronic device according to claim 4, characterized in that, When the dominant crystal plane of the perovskite grain is the (100) crystal plane, the average thickness of the (100) crystal plane of the perovskite grain in the normal direction is D. (100) And 700Å≤D (100) ≤1000Å, can be selected as 750Å≤D (100) ≤950Å, or When the dominant crystal plane of the perovskite grain is the (111) crystal plane, the average thickness of the (111) crystal plane of the perovskite grain in the normal direction is D. (111) And 600Å≤D (111) ≤1000Å, can be selected as 650Å≤D (111) ≤950Å.

6. The optoelectronic device according to any one of claims 1 to 5, characterized in that, In the one-dimensional integral curve of the GIWAXS two-dimensional diffraction pattern of the perovskite layer, the ratio of the integral area of ​​the diffraction peaks of the dominant crystal plane of the metal iodide to that of the dominant crystal plane of the perovskite grain is 0.5% to 5.5%, which can be selected as 0.5% to 5%.

7. The optoelectronic device according to any one of claims 1 to 6, characterized in that, At least a portion of the metal iodide has a thickness of 20 Å to 50 Å on the outer surface of the perovskite grain.

8. The optoelectronic device according to any one of claims 1 to 7, characterized in that, At least a portion of the metal iodide is located at the grain boundaries of the perovskite grains.

9. The optoelectronic device according to any one of claims 1 to 8, characterized in that, The perovskite layer has a first surface and a second surface that are opposite to each other in the thickness direction of the perovskite layer; wherein at least a portion of the metal iodide is located on at least one of the first surface and the second surface.

10. The optoelectronic device according to any one of claims 1 to 9, characterized in that, The perovskite layer has a first surface and a second surface that are opposite to each other in the thickness direction of the perovskite layer; the distribution content of the metal iodide at the grain boundaries of the perovskite grains is higher than the sum of the distribution content on the first surface and the second surface of the perovskite layer.

11. The optoelectronic device according to any one of claims 1 to 10, characterized in that, The perovskite grains on which the metal iodide is distributed on the outer surface are designated as the first perovskite grains; The first perovskite grain accounts for 60% to 100% of the total number of perovskite grains in the perovskite layer, and can be selected as 90% to 100%.

12. The optoelectronic device according to any one of claims 1 to 11, characterized in that, The metal iodide contains one or more of lead, tin, and chromium.

13. The optoelectronic device according to any one of claims 1 to 12, characterized in that, The perovskite layer includes a first perovskite material, which includes lead and iodine.

14. The optoelectronic device according to claim 13, characterized in that, The first perovskite material includes at least two of the elements iodine, bromine, and chlorine.

15. The optoelectronic device according to any one of claims 1 to 14, characterized in that, The perovskite layer contains a modifier, which includes diC. 2-6 Alkylamine hydrochloride and diC 2-6 One or more of alkylamine thiocyanates; Optionally, the modifier includes one or more of dipropylamine hydrochloride, dibutylamine hydrochloride, diethylamine thiocyanate, dipropylamine thiocyanate, and dibutylamine thiocyanate.

16. The optoelectronic device according to any one of claims 1 to 15, characterized in that, In a direction perpendicular to the thickness of the perovskite layer, the area of ​​the perovskite layer is greater than or equal to 0.09 cm². 2 .

17. The optoelectronic device according to any one of claims 1 to 16, characterized in that, The optoelectronic devices include photovoltaic devices or light-emitting devices.

18. The optoelectronic device according to any one of claims 1 to 17, characterized in that, The optoelectronic device is a photovoltaic device, which includes a solar cell; the solar cell includes the perovskite layer.

19. The optoelectronic device according to any one of claims 1 to 18, characterized in that, The optoelectronic device includes a solar cell, which is a multi-junction solar cell. The multi-junction solar cell includes a first cell unit, which includes the perovskite layer.

20. The optoelectronic device according to claim 19, characterized in that, The multijunction solar cell further includes a second cell stacked with the first cell cell; the second cell cell and the first cell cell are connected by an interconnect layer, or the second cell cell and the first cell cell are isolated by an insulating layer; the second cell cell includes a light-absorbing layer, and the light-absorbing layer and the perovskite layer have different band gaps.

21. The optoelectronic device according to claim 20, characterized in that, The light-absorbing layer in the second battery cell includes a semiconductor active material, which includes one or more of the following: a second perovskite material, a silicon-containing semiconductor material, copper zinc tin sulfide, copper zinc tin selenide, copper zinc tin selenide sulfide, copper indium gallium selenide, copper indium gallium diselenide, copper indium selenide, cadmium telluride, gallium arsenide, and organic active materials.

22. The optoelectronic device according to any one of claims 19 to 21, characterized in that, The multi-junction solar cell includes a first electrode, a perovskite layer, an interconnect layer, a light-absorbing layer, and a second electrode stacked together; wherein the interconnect layer is located between the perovskite layer and the light-absorbing layer; the first electrode is located on the side of the perovskite layer away from the interconnect layer, and the second electrode is located on the side of the light-absorbing layer away from the interconnect layer.

23. The optoelectronic device according to any one of claims 19 to 21, characterized in that, The multi-junction solar cell includes a first electrode, a perovskite layer, a third electrode, an insulating layer, a fourth electrode, a light-absorbing layer, and a second electrode stacked together; wherein the third electrode, the insulating layer, and the fourth electrode are stacked between the perovskite layer and the light-absorbing layer, the third electrode is disposed on the side of the insulating layer facing the perovskite layer, the fourth electrode is disposed on the side of the insulating layer facing the light-absorbing layer, the first electrode is located on the side of the perovskite layer away from the third electrode, and the second electrode is located on the side of the light-absorbing layer away from the fourth electrode.

24. The optoelectronic device according to any one of claims 1 to 23, characterized in that, The optoelectronic device is a photovoltaic device; the optoelectronic device satisfies one or more of the following characteristics: (a1) The perovskite layer is contained in the inverse or formal structure of the optoelectronic device; (a2) The optoelectronic device includes a first charge transport layer and a second charge transport layer, wherein the perovskite layer is stacked between the first charge transport layer and the second charge transport layer; wherein, one of the first charge transport layer and the second charge transport layer is a hole transport layer and the other is an electron transport layer.

25. A method for fabricating an optoelectronic device, characterized in that, Includes the following steps: A perovskite precursor solution is prepared; wherein the perovskite precursor solution includes perovskite precursor raw materials and solvent, and the perovskite precursor solution also includes a metal iodide additive, the metal iodide additive having a dominant crystal face; optionally, the perovskite precursor solution also includes a regulator. The perovskite precursor solution was coated and vacuum dried to remove some of the solvent, thus preparing a perovskite intermediate phase film layer. The perovskite mesophase film layer is laser-annealed to form a perovskite layer; wherein, the laser annealing includes annealing at a first temperature and a second temperature, wherein the first temperature is lower than the second temperature; The formed perovskite layer comprises perovskite grains, and at least a portion of the outer surfaces of the perovskite grains are distributed with metal iodides; in the GIWAXS two-dimensional diffraction pattern of the perovskite layer, the orientation angle between the dominant crystal plane of the metal iodide and the dominant crystal plane of the perovskite grain is less than or equal to 5°; wherein, GIWAXS refers to grazing wide-angle X-ray scattering; the dominant crystal plane refers to the crystal plane corresponding to the strongest diffraction signal of the corresponding phase in the GIWAXS two-dimensional diffraction pattern.

26. The method for fabricating an optoelectronic device according to claim 25, characterized in that, The method for fabricating the optoelectronic device satisfies one or more of the following characteristics: (b1) The vacuum drying is carried out at a temperature of 20°C to 30°C, a pressure of 80Pa to 150Pa, and a duration of 15s to 25s. Optionally, after the vacuum drying process, the mass percentage of the residual solvent is 10% to 20%, based on the initial solvent content before vacuum drying. (b2) The regulator includes diC 2-6 Alkylamine hydrochloride and diC 2-6 One or more of alkylamine thiocyanates; Optionally, the regulator includes one or more of dipropylamine hydrochloride, dibutylamine hydrochloride, diethylamine thiocyanate, dipropylamine thiocyanate, and dibutylamine thiocyanate; (b3) The molar percentage of the regulator relative to the perovskite precursor raw material is 0 to 3.5%, and can be selected as 0.45% to 3.5%; (b4) The first temperature is 85℃~95℃, and the second temperature is 95℃~105℃; Optionally, the laser annealing time at the first temperature is 1s to 5s, and the laser annealing time at the second temperature is 5s to 15s; (b5) The laser power for laser annealing at the first temperature is 100W~200W, and the laser power for laser annealing at the second temperature is 550W~650W.

27. An electrical appliance, characterized in that, It includes at least one of the optoelectronic devices according to any one of claims 1 to 24 and the optoelectronic devices prepared by the preparation method of any one of claims 25 to 26.

28. A power generation device, characterized in that, It includes at least one of the optoelectronic devices according to any one of claims 1 to 24 and optoelectronic devices prepared by the method of preparing the optoelectronic device according to any one of claims 25 to 26.

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