Array materials and their preparation methods, solar cells, photovoltaic modules and photovoltaic systems

Abstract

The present invention relates to an array material and a preparation method thereof, a solar cell, a photovoltaic module and a photovoltaic system. The array material contains an array structure formed by nanorods. The nanorods include a rod core and a shell layer located on at least part of the surface of the rod core. The component of the rod core includes a p-type semiconductor material, and the component of the shell layer includes MoO3. When the array material is used as a hole transport material to prepare a solar cell, while ensuring good hole transport ability, the stability of the solar cell can be improved, and further the photoelectric conversion efficiency of the solar cell can be improved.

Description

Technical Field

[0001] The present invention relates to the technical field of solar cells, and particularly relates to an array material and a preparation method thereof, a solar cell, a photovoltaic module and a photovoltaic system. Background Art

[0002] Perovskite solar cells have many excellent optoelectronic properties, such as high light absorption coefficient, long carrier lifetime and long diffusion length, and have become the leading ones in the third generation of new solar cells. Among them, inverted perovskite solar cells have attracted more and more attention due to their good stability and low hysteresis effect, mainly including normal perovskite solar cells and inverted perovskite solar cells.

[0003] Metal oxides such as nickel oxide are commonly used hole transport layer materials when preparing inverted perovskite solar cells. However, traditional hole transport layer materials are unstable and have too many defects, which will reduce the photoelectric conversion efficiency and stability of solar cells.

[0004] Therefore, the traditional technology still needs to be improved. Summary of the Invention

[0005] Based on this, it is necessary to provide an array material and a preparation method thereof, a solar cell, a photovoltaic module and a photovoltaic system, aiming to improve the photoelectric conversion efficiency of solar cells.

[0006] The present application is implemented by the following technical solutions.

[0007] In the first aspect of the present application, an array material is provided. The array material contains an array structure formed by nanorods. The nanorods include a rod core and a shell layer located on at least part of the surface of the rod core: the component of the rod core includes a p-type semiconductor material, and the component of the shell layer includes MoO3.

[0008] The component of the above array material contains an array structure formed by nanorods. The nanorods include a rod core and a shell layer located on at least part of the surface of the rod core. The component of the rod core includes a p-type semiconductor material, and the component of the shell layer includes MoO3. When the array material is used as an electron transport material to prepare a solar cell, on the one hand, in the array structure formed by the nanorods, the nanorods have higher crystallinity, which is beneficial to improving the hole transport performance, and the array structure is a light trapping structure, which increases the optical path of photons, thereby increasing the light absorption amount; on the other hand, the nanorods have a p-type semiconductor material as the rod core, and a MoO3 shell layer is provided on at least part of the surface of the rod core. Using MoO3 as the shell can prevent the reaction between perovskite and the hydroxyl group on the surface of the p-type semiconductor material to achieve a passivation effect. In this way, while ensuring good hole transport ability, the stability of the solar cell is improved, and further the photoelectric conversion efficiency of the solar cell is improved.

[0009] In some embodiments, the length of the rod core is 30 nm to 100 nm.

[0010] In some embodiments, the array material has a porous structure, and the pore diameter of at least some of the pores in the porous structure is 100 nm to 500 nm.

[0011] By controlling the pore diameter of the porous structure, the pore size of the array structure in the array material can exactly meet the requirements for charge passage, further improving the hole transport ability of the array material.

[0012] In some embodiments, in the nanorod, the thickness of the shell layer is 10 nm to 50 nm;

[0013] Optionally, the thickness of the shell layer is 10 nm to 40 nm;

[0014] Optionally, the thickness of the shell layer is 15 nm to 30 nm.

[0015] In some embodiments, the p-type semiconductor material is a p-type semiconductor oxide.

[0016] In some embodiments, the p-type semiconductor material includes at least one of nickel oxide, copper oxide, cuprous oxide, copper cyanide, and copper iodide.

[0017] In a second aspect of the present application, there is provided a method for preparing the array material of the first aspect, including the following steps:

[0018] Subject the precursor of the p-type semiconductor material to a first deposition treatment, and then an annealing treatment to obtain the rod core;

[0019] Subject the precursor of MoO3 to a second deposition treatment on the surface of the rod core to form the shell layer, thereby obtaining the array material.

[0020] In a third aspect of the present application, there is provided an application of the array material of the first aspect as a hole transport material.

[0021] In some embodiments, the above-mentioned array material is used as a hole transport material in the preparation of solar cells.

[0022] In a fourth aspect of the present application, there is provided a solar cell, which includes a hole transport layer and a perovskite layer arranged in sequence, and the hole transport layer includes the array material of the first aspect.

[0023] In some embodiments, the hole transport layer includes a first hole transport film and a second hole transport film arranged in sequence, and the second hole transport film is disposed between the first hole transport film and the perovskite layer;

[0024] The components of the first hole transport layer include a p-type semiconductor material, and the components of the second hole transport layer include the array material.

[0025] When applying the above array material to a perovskite solar cell, by providing a first hole transport layer with hole transport ability between the second hole transport layer and the perovskite layer, the leakage current caused by the direct contact between the array material and the perovskite layer can be further avoided, and the efficiency of the solar cell can be further improved.

[0026] In some embodiments, the thickness of the second hole transport layer is 30 nm to 120 nm;

[0027] Optionally, the thickness of the second hole transport layer is 30 nm to 100 nm.

[0028] By controlling the thickness of the second hole transport layer, while ensuring excellent hole transport ability, electron loss can be avoided, and the efficiency of the solar cell can be further improved.

[0029] In some embodiments, the first hole transport layer satisfies at least one of the following features (a) to (c):

[0030] (a) The thickness of the first hole transport layer is 20 nm to 50 nm;

[0031] Optionally, the thickness of the first hole transport layer is 20 nm to 40 nm;

[0032] (b) The p-type semiconductor material in the first hole transport layer includes at least one of nickel oxide, copper oxide, cuprous oxide, copper cyanide, and copper iodide;

[0033] (c) The p-type semiconductor material in the first hole transport layer is the same as the p-type semiconductor material in the array material.

[0034] In some embodiments, the perovskite layer satisfies at least one of the following features (e) to (f):

[0035] (e) The bandgap of the perovskite layer is 1.20 eV to 2.30 eV;

[0036] (f) The thickness of the perovskite layer is 400 nm to 1000 nm.

[0037] In a fifth aspect of the present application, a photovoltaic module is provided, including the solar cell of the fourth aspect of the present application.

[0038] In a sixth aspect of the present application, a photovoltaic module is provided, including the photovoltaic module of the fifth aspect of the present application. Description of the Drawings

[0039] By reading the following detailed description of the preferred embodiments, various other advantages and benefits will become clear to those of ordinary skill in the art. The drawings are only for the purpose of illustrating the preferred embodiments and are not considered to be a limitation of the present application. Moreover, in all the drawings, the same reference numerals are used to represent the same components. In the drawings:

[0040] Figure 1 is an electron micrograph of the array material obtained in an embodiment of the present application. Specific Embodiments

[0041] To make the above objects, features, and advantages of the present invention more obvious and understandable, the following detailed description of the specific embodiments of the present invention is provided. Many specific details are set forth in the following description in order to fully understand the present invention. However, the present invention can be implemented in many other ways different from those described herein, and those skilled in the art can make similar improvements without departing from the connotation of the present invention. Therefore, the present invention is not limited by the specific embodiments disclosed below.

[0042] In the present invention, unless otherwise clearly defined and limited, the terms "mounted", "connected", "connected to", "fixed", etc. shall be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral body; it can be a mechanical connection or an electrical connection; it can be directly connected or indirectly connected through an intermediate medium, and it can be the communication inside two elements or the interaction relationship between two elements, unless otherwise clearly limited. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0043] In addition, the terms "first" and "second" are only used for descriptive purposes and cannot be understood as indicating or implying relative importance or implicitly indicating the quantity of the indicated technical features. Thus, the features defined with "first" and "second" may explicitly or implicitly include at least one of such features. In the description of the present invention, the meaning of "a plurality" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

[0044] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by those of ordinary skill in the technical field to which the present invention belongs. The terms used in the specification of the present invention herein are only for the purpose of describing specific embodiments and are not intended to limit the present invention. The term "and / or" used herein includes any and all combinations of one or more of the related listed items.

[0045] In summary, conventional hole transport layer materials are unstable and have too many defects, which will reduce the photoelectric conversion efficiency and stability of solar cells. In conventional technology, the stability of hole transport layer materials is improved by passivating the hole transport layer materials.

[0046] The technicians of this application have found that in traditional technology, a polymer film layer is often loaded on the surface of the hole transport layer material to improve the stability of the hole transport layer material. Generally, a wet coating technology is required, which can easily cause uneven distribution of the film and reduce the efficiency of the solar cell.

[0047] Based on this, the technical personnel of this application, after a lot of creative research, obtained the array material in this application that can improve the photoelectric conversion efficiency of solar cells.

[0048] An embodiment of the present application provides an array material, which contains an array structure constructed of nanorods. The nanorods include a rod core and a shell layer located on at least a portion of the surface of the rod core. The component of the rod core includes a p-type semiconductor material, and the component of the shell layer includes MoO3.

[0049] The components of the above-mentioned array material contain an array structure formed by nanorods, the nanorods include a rod core and a shell layer located on at least part of the surface of the rod core, the rod core component includes a p-type semiconductor material, and the shell layer component includes MoO3. When the array material is used as an electron transport material to prepare a solar cell, on the one hand, the nanorods have a higher crystallinity in the array structure, which is conducive to improving the hole transport performance, and the array structure is a light trapping structure, which increases the optical path of the added photons, thereby increasing the light absorption; on the other hand, the nanorods use p-type semiconductor materials as the rod core, and a MoO3 shell layer is provided on at least part of the surface of the rod core. Using MoO3 as a shell can prevent the perovskite from reacting with the hydroxyl group on the surface of the p-type semiconductor material to achieve a passivation effect. In this way, while ensuring good hole transport capacity, the stability of the solar cell is improved, thereby improving the photoelectric conversion efficiency of the solar cell.

[0050] The rod core comprises rod heads at two ends and a rod body located between the rod heads at the two ends. Optionally, a shell layer is provided on the surface of the rod head at at least one end of the rod core.

[0051] In some of the embodiments, a shell layer is provided on the surface of the rod body and at least one end of the rod head in the rod core.

[0052] In some embodiments, the length of the rod core is 30 nm to 100 nm.

[0053] It is understood that the length of a nanorod is simply the straight-line distance between the two ends of the nanorod.

[0054] In the above “30 nm to 100 nm”, the value can be either of the two endpoints or any value between the two endpoints. Non-limiting examples include, but are not limited to: 30 nm, 35 nm, 40 nm, 45 nm, 50 nm, 55 nm, 60 nm, 65 nm, 70 nm, 75 nm, 80 nm, 85 nm, 90 nm, 95 nm, 100 nm.

[0055] In some embodiments, the array material has a porous structure, and the pore diameter of at least some of the pores in the porous structure is 100 nm to 500 nm.

[0056] In the above array material, some of the nanorods extend and intersect with each other, forming interconnected channels or pores, thereby constituting a porous structure. At this time, the array material is a porous array material. By controlling the pore diameter of at least some of the pores in the porous structure to be 100 nm to 500 nm, the void size of the array structure in the array material can just meet the requirements for charge passing, further improving the hole transport ability of the array material.

[0057] Based on the total number of pores in the porous structure, the proportion of the number of pores with a pore diameter of 100 nm to 500 nm is P. Optionally, P satisfies: 0.01% ≤ P ≤ 100%.

[0058] Optionally, P ≥ 0.01%; further, P ≥ 0.1%; further, P ≥ 1%; further, P ≥ 5%; further, P ≥ 10%; further, P ≥ 20%; further, P ≥ 30%; further, P ≥ 40%; further, P ≥ 50%; further, P ≥ 60%; further, P ≥ 70%; further, P ≥ 90%; further, P ≥ 90%; further, 90 ≤ P ≤ 100%.

[0059] In the above “100 nm to 500 nm”, the value can be either of the two endpoints or any value between the two endpoints. Non-limiting examples include, but are not limited to: 100 nm, 150 nm, 200 nm, 250 nm, 300 nm, 350 nm, 400 nm, 450 nm, 500 nm.

[0060] In some embodiments, in the core-shell material, the thickness of the shell layer is 10 nm to 50 nm.

[0061] In some embodiments, in the core-shell material, the thickness of the shell layer is 10 nm to 40 nm.

[0062] In some embodiments, in the core-shell material, the thickness of the shell layer is 15 nm to 30 nm.

[0063] In some embodiments, the p-type semiconductor material is a p-type semiconductor oxide.

[0064] In some of these embodiments, the p-type semiconductor material includes at least one of nickel oxide, copper oxide, cuprous oxide, copper cyanide, and copper iodide.

[0065] One embodiment of the present application provides an application of the above array material as a hole transport material.

[0066] Furthermore, an application of the above array material as a hole transport material in the preparation of a solar cell.

[0067] Furthermore, the above solar cell is a perovskite solar cell.

[0068] Another embodiment of the present invention provides a preparation method of the above array material, including the following steps S10 to S20.

[0069] Step S10: The precursor of the p-type semiconductor material is subjected to a first deposition treatment and then an annealing treatment to obtain a rod core.

[0070] In some of these embodiments, the precursor of the p-type semiconductor material includes Ni and oxygen, and the above first deposition treatment is carried out using a Ni target in an oxygen atmosphere.

[0071] Furthermore, the above first deposition treatment uses radio frequency magnetron sputtering. The specific steps are as follows:

[0072] Using a metal Ni target as the sputtering source, radio frequency magnetron sputtering is carried out from bottom to top for deposition on the substrate, controlling the normal direction of the substrate surface to form a 70° angle with the vertical connection direction between the sputtering source and the substrate, and at the same time, oxygen is introduced into the chamber for deposition.

[0073] In some of these embodiments, the temperature of the above annealing treatment is 250 °C to 500 °C, and the time is 10 min to 40 min.

[0074] Step S20: The precursor of MoO3 is subjected to a second deposition treatment on the surface of the rod core to form a shell layer, obtaining the above array material.

[0075] In some of these embodiments, the precursor of MoO3 includes molybdenum hexacarbonyl Mo(CO)6 and oxygen.

[0076] In some of these embodiments, the second deposition treatment uses atomic layer deposition technology (ALD).

[0077] One embodiment of the present application further provides a solar cell, which includes a hole transport layer and a perovskite layer arranged in sequence, and the hole transport layer includes the above array material.

[0078] In some of these embodiments, the hole transport layer includes a first hole transport film and a second hole transport film arranged in sequence, and the second hole transport film is disposed between the first hole transport film and the perovskite layer.

[0079] The component of the first hole transport film includes a p-type semiconductor material, and the component of the second hole transport film includes the above-mentioned array material.

[0080] When applying the above-mentioned array material to a perovskite solar cell, by arranging a first hole transport film with hole transport ability between the second hole transport film and the perovskite layer, the leakage current caused by the direct contact between the array material and the perovskite layer can be further avoided, and the efficiency of the solar cell can be further improved.

[0081] In some of these embodiments, the thickness of the above-mentioned second hole transport film is 30 nm to 120 nm.

[0082] In some of these embodiments, the thickness of the above-mentioned second hole transport film is 30 nm to 100 nm.

[0083] By controlling the thickness of the second hole transport film, while ensuring excellent hole transport ability, electron loss can be avoided, and the efficiency of the solar cell can be further improved.

[0084] In some of these embodiments, the porosity of the first hole transport film is smaller than that of the second hole transport film.

[0085] In some of these embodiments, the thickness of the above-mentioned first hole transport film is 20 nm to 50 nm.

[0086] In some of these embodiments, the thickness of the above-mentioned first hole transport film is 20 nm to 40 nm.

[0087] By controlling the thickness of the first hole transport film, while ensuring that the hole transport layer has excellent hole transport ability, electron loss can be avoided, and the efficiency of the solar cell can be further improved.

[0088] In some of these embodiments, the p-type semiconductor material in the first hole transport film includes at least one of nickel oxide, copper oxide, cuprous oxide, copper cyanide, and copper iodide.

[0089] The p-type semiconductor material in the above-mentioned base film and the p-type semiconductor material in the array material may be the same or different.

[0090] In some of these embodiments, the p-type semiconductor material in the above-mentioned first hole transport film is the same as the p-type semiconductor material in the array material. In this way, the energy level matching degree between the first hole transport film and the second hole transport film can be further improved.

[0091] In some of these embodiments, the band gap of the above perovskite layer is 1.20 eV to 2.30 eV.

[0092] The band gap of the perovskite layer can be measured by common testing methods in the art. For example, it can be measured using the XPS data processing function in Avantage software.

[0093] In some of these embodiments, the above perovskite layer includes a perovskite material. Specifically, the chemical formula satisfies ABX3 or A2CDX6; wherein, A is an inorganic cation or an organic ammonium cation or a mixture of the two, and can be at least one of formamidinium ion (FA), methylammonium ion (MA), and Cs; B is an inorganic metal cation, and can be at least one of Pb ion and Sn ion; C is a noble metal cation, and is commonly Ag + ; D is a heavy metal or rare metal cation, and can be bismuth cation Bi 3+ antimony cation Sb 3+ and indium cation In 3+ at least one of; X is oxygen or a halogen element, and can be at least one of O, Br, and I.

[0094] In some of these embodiments, the thickness of the perovskite layer is 400 nm to 1000 nm.

[0095] In some of these embodiments, the solar cell further includes a conductive base layer and an electron transport layer. The electron transport layer is disposed on the side of the perovskite layer away from the hole transport layer, and the conductive base layer is disposed on the side of the first hole transport film away from the second hole transport film.

[0096] In some of these embodiments, the components of the electron transport layer can be common electron transport materials in the art. Non-limiting examples include: [6,6]-phenyl-C61-butyric acid methyl ester (PC61BM), [6,6]-phenyl-C71-butyric acid methyl ester (PC71BM), fullerene C60 (C60), fullerene C70 (C70), tin dioxide (SnO2), zinc oxide (ZnO), etc.

[0097] In some of these embodiments, the material of the above transparent conductive base layer can be FTO, ITO, AZO, BZO, IZO glass.

[0098] The above solar cell further includes an electrode on the surface of the electron transport layer away from the hole transport layer. The electrode can use common electrode materials in the art, including but not limited to the following materials: Ag, Cu, C, Au, Al, ITO, AZO, BZO, IZO, IWO, etc.

[0099] One embodiment of the present invention further provides a photovoltaic module, and the photovoltaic module includes the above solar cell.

[0100] The above-mentioned solar cell has high light conversion efficiency and good stability, which can improve the efficiency of photovoltaic modules.

[0101] In the above-mentioned photovoltaic module, one or more solar cells are included, which can be selected according to specific application scenarios; further, the above-mentioned photovoltaic module includes a plurality of solar cells, and the plurality of solar cells are connected in series or in parallel to form a cell sheet.

[0102] In some embodiments, the above-mentioned photovoltaic module further includes a photovoltaic glass layer, an adhesive layer, and a backsheet.

[0103] Adhesive layers are respectively provided on two surfaces of the cell sheet. A backsheet is provided on the surface of one of the adhesive layers away from the cell sheet, and a photovoltaic glass layer is provided on the surface of the other adhesive layer away from the cell sheet.

[0104] The photovoltaic glass layer and the backsheet are used to protect the solar cell, for sealing, insulation, and waterproofing; the adhesive layer serves to bond the photovoltaic glass layer to the cell sheet and bond the backsheet to the cell sheet.

[0105] Optionally, the material of the photovoltaic glass layer is tempered glass, the material of the backsheet is TPT (polyvinyl fluoride) or TPE (thermoplastic elastomer), and the material of the adhesive layer is EVA (ethylene-vinyl acetate copolymer).

[0106] Further, the above-mentioned photovoltaic module further includes a junction box and an outer frame.

[0107] The junction box is used to protect the power generation system of the entire photovoltaic module. It is equivalent to a current transfer station. When a cell sheet has a short circuit, the junction box will automatically disconnect the short-circuited cell string.

[0108] The outer frame can play a role in supporting and protecting the entire photovoltaic module. The frame can be made of aluminum alloy, with excellent strength and corrosion resistance.

[0109] Further, silicone is used to bond and seal the connection between the frame and other parts of the photovoltaic module. The photovoltaic module can convert solar energy into electrical energy, which can be sent to a storage battery for storage or used to drive a load.

[0110] In some embodiments, the above-mentioned photovoltaic module is a solar panel.

[0111] An embodiment of the present application further provides a photovoltaic system, including the above-mentioned photovoltaic module.

[0112] The photovoltaic system utilizes the photovoltaic effect of the solar cells in the above-mentioned photovoltaic module to directly convert solar radiant energy into electrical energy, with high efficiency; further, the above-mentioned photovoltaic system is a photovoltaic power generation system.

[0113] Photovoltaic modules are the core part of a photovoltaic power generation system. In the above photovoltaic system, one or more photovoltaic modules are included, which can be selected according to specific application scenarios. Further, when multiple photovoltaic modules are included in the above photovoltaic system, the multiple photovoltaic modules form a photovoltaic array.

[0114] The above photovoltaic system can be an independent photovoltaic power generation system or a grid-connected photovoltaic power generation system.

[0115] The independent photovoltaic power generation system includes a photovoltaic array, a battery pack, a charge controller, a power electronic converter (inverter), a load, etc. Its working principle is that the solar radiation energy is first converted into electrical energy by the photovoltaic array, then converted by the power electronic converter and supplied to the load. At the same time, the excess electrical energy is stored in the energy storage device in the form of chemical energy through the charge controller. In this way, when the sunlight is insufficient, the energy stored in the battery can be converted into AC 220V, 50Hz electrical energy through the power electronic inverter, filtering and power frequency transformer boost for AC load use.

[0116] The grid-connected photovoltaic power generation system includes a photovoltaic array, a high-frequency DC / DC boost circuit, a power electronic converter (inverter) and system monitoring. Its working principle is that after the solar radiation energy is converted by the photovoltaic array, it is then converted into high-voltage direct current through high-frequency DC conversion, and then inverted by the power electronic inverter and output to the grid as a sinusoidal alternating current with the same phase and frequency as the grid voltage.

[0117] The above two photovoltaic power generation systems have their own characteristics and can be selected according to specific application scenarios.

[0118] The present invention will be described below in conjunction with specific embodiments, but the present invention is not limited to the following embodiments. It should be understood that the appended claims define the scope of the present invention. Under the guidance of the inventive concept of the present invention, those skilled in the art should realize that certain changes made to the embodiments of the present invention will be covered by the spirit and scope of the claims of the present invention.

[0119] The following are specific embodiments. Specific Embodiment

[0121] Embodiment 1

[0122] (1) Preparation of solar cells, the specific steps are as follows:

[0123] 1. Cleaning of FTO conductive glass: Put the 2.0 cm × 2.0 cm FTO conductive glass into deionized water, acetone, and isopropanol and ultrasonically clean for 10 minutes in sequence, and then dry and reserve.

[0124] 2. Preparation of the base film: The FTO glass was treated with ultraviolet ozone. A 0.15 M nickel nitrate hexahydrate methanol precursor solution was prepared. 80 μL of the precursor solution was spin-coated on the FTO glass at a spin-coating speed of 6K rpm for 30 s, and then annealed at 80 °C for 10 min, further heated to 345 °C and maintained for 30 min, and cooled to 100 °C to form a NiOx film layer on the FTO, obtaining the FTO / NiOx sample.

[0125] Using a scanning electron microscope (SEM), the cross-section of the sample to be measured was placed in the test instrument. At a magnification of 10,000 times, the thickness of the NiOx film layer was measured and denoted as T1.

[0126] 3. Preparation of the NiOx nanorod array: Using a sputtering source metal Ni target, by means of radio frequency magnetron sputtering technology, sputtering from bottom to top, making the normal direction of the surface of the NiOx film of the FTO / NiOx sample form a 70° angle with the vertical connection direction between the sputtering source and the sample surface. 20 mTorr of oxygen (purity 100%) was introduced into the chamber, and a NiOx nanorod core was obtained by reactive sputtering on the surface of the NiOx film. The length of the NiOx nanorod core was about 100 nm (the length of the nanorod core was measured by placing it in a scanning electron microscope SEM at a magnification of 10,000 times), and then annealed at 300 °C for 60 min to form a NiOx nanorod core array on the NiOx film layer.

[0127] MoO3 coating on the NiOx nanorod core array: Using molybdenum hexacarbonyl (Mo(CO)6) and pure oxygen (purity 99.999%) as precursor sources for atomic layer deposition technology (ALD), the pipeline for transporting the precursor was heated to 40 °C to prevent its condensation during transportation: First, the Mo(CO)6 precursor was introduced for 3 s (nitrogen as the carrier gas), purged with nitrogen for 5 s, then oxygen plasma was introduced for 3 s, and purged with nitrogen for 5 s, which was regarded as one cycle. The flow rates of the incoming oxygen plasma and the purging gas were 250 sccm and 300 sccm respectively. After 100 such cycles, a MoO3 shell layer was formed on the surface of the NiOx nanorod core array, obtaining the nanorod array material film.

[0128] Among them, the thickness of the MoO3 shell layer and the overall thickness of the formed nanorod array material film were measured by placing the nanorod array material film in a scanning electron microscope (SEM) and denoted as T2 and T3 respectively. For details, please refer to Table 1.

[0129] Among them, the prepared nanorod array material film was observed under a microscope, and the electron micrograph of the nanorod array material is as Figure 1 shown, and the nanorods and array structure can be clearly seen.

[0130] 4. Preparation of perovskite light-absorbing layer: Spin-coat the perovskite precursor solution (FAPbI3) on the nanorod array material film at a speed of 3000 rpm to 5000 rpm for 40 s. About 10 s after the start of spin-coating, add 300 μL to 600 μL of the anti-solvent chlorobenzene. Then place the film on a hot plate and anneal it at 100 °C to 120 °C for 60 min to obtain a perovskite layer with a thickness of 500 nm.

[0131] 5. Preparation of electron transport layer: When the evaporation vacuum degree reaches below 5×10 -4 Pa, evaporate 30 nm of the electron transport layer C60 on the surface of the perovskite light-absorbing layer at a rate of 0.05 A / s.

[0132] 6. Preparation of metal counter electrode: When the evaporation vacuum degree reaches below 5×10 -4 Pa, evaporate 80 nm of the metal back electrode Ag on the surface of the electron transport layer at a rate of 0.1 A / s to obtain a p-i-n type perovskite solar cell.

[0133] (2) Performance test:

[0134] Use Keithley 2400 SMU to perform device tests on the prepared perovskite solar cells under a light source of AM 1.5G solar irradiation at 100 mW / cm 2 and calculate the energy conversion efficiency Eff according to the following formula:

[0135] Eff = Pout / Popt = Voc × Jsc × (Vmpp × Jmpp) / (Voc × Jsc) = Voc × Jsc × FF

[0136] where Pout, Popt, Vmpp, and Jmpp are the working output power, incident light power, maximum power point voltage, and maximum power point current of the battery, respectively, and Voc, Jsc, and FF are the open-circuit voltage, short-circuit current density, and fill factor, respectively. The specific results are shown in Table 1.

[0137] Examples 2 - 7

[0138] Examples 2 - 7 are basically the same as Example 1, except that in the steps of preparing the NiOx nanorod array, the sputtering time is adjusted to control the length of the formed NiOx nanorod cores, and the thickness T2 of the MoO3 shell layer is kept the same as that in Example 1, and finally, nanorod array material films with different thicknesses T3 are obtained. See Table 1 for details.

[0139] The remaining steps are the same as those in Example 1.

[0140] Examples 8 - 10

[0141] Examples 8 to 10 are basically the same as Example 1, except that: the thickness T2 of the MoO3 shell layer is adjusted, and the sputtering time in the steps of preparing the NiOx nanorod array is correspondingly adjusted so that the thickness T3 of the obtained nanorod array material film is the same as that in Example 1. See Table 1 for details.

[0142] The remaining steps are the same as those in Example 1.

[0143] Examples 11 to 13

[0144] Examples 11 to 13 are basically the same as Example 1, except that: in the steps of preparing the NiOx film layer, the spin coating thickness is adjusted to obtain NiOx film layers with different thicknesses T1. See Table 1 for specific parameters.

[0145] The remaining steps are the same as those in Example 1.

[0146] Comparative Example 1

[0147] Comparative Example 1 is basically the same as Example 1, except that: the steps of preparing the NiOx nanorod core array and coating the NiOx nanorod core array with MoO3 are omitted, and the thickness of the NiOx film layer = the thickness of the NiOx film layer in Example 1 + the thickness of the nanorod array material film. See Table 1 for details.

[0148] The remaining steps are the same as those in Example 1.

[0149] Comparative Example 2

[0150] Comparative Example 2 is basically the same as Example 1, except that: the steps of preparing the NiOx nanorod core array are omitted, and a MoO3 coating layer is directly formed on the surface of the NiOx film layer. The thickness T2 of the MoO3 coating layer is the same as that in Example 1, and the thickness of the NiOx film layer + the MoO3 coating layer = the thickness of the NiOx film layer in Example 1 + the thickness of the nanorod array material film. See Table 1 for details.

[0151] The remaining steps are the same as those in Example 1.

[0152] Comparative Example 3

[0153] Comparative Example 3 is basically the same as Example 1, except that: the steps of coating the NiOx nanorod core array with MoO3 are omitted, the thickness T1 of the NiOx film layer is the same as that in Example 1, and the thickness of the NiOx film layer + the NiOx nanorod core array = the thickness of the NiOx film layer in Example 1 + the thickness of the nanorod array material film. See Table 1 for details.

[0154] The remaining steps are the same as those in Example 1.

[0155] The relevant physical parameters and test results in each embodiment and comparative example are shown in Table 1: Among them, T1 is the thickness of the NiOx film layer, T2 is the thickness of the MoO3 shell layer, and T3 is the total thickness of the nanorod array material film formed after MoO3 coats the NiOx nanorod core array.

[0156] Table 1

[0157]

[0158]

[0159] Note: " / " represents the absence of this structure. In Comparative Example 1, the nanorod array material film with MoO3 coating the NiOx nanorod core array was not formed. In Comparative Example 2, the MoO3 coating layer was formed, but the nanorod array material film with MoO3 coating the NiOx nanorod core array was not formed. In Comparative Example 3, the NiOx nanorod core array was formed, but the nanorod array material film with MoO3 coating the NiOx nanorod core array was not formed.

[0160] It can be seen from the experimental results in the above table that when the array material of the present application is used as a hole transport material to prepare a solar cell, while ensuring good hole transport ability, it can improve the stability of the solar cell, and further improve the photoelectric conversion efficiency of the solar cell.

[0161] The technical features of the above-described embodiments can be combined arbitrarily. For the sake of brevity of description, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, it should be considered as the scope described in this specification.

[0162] The above-described embodiments only represent several implementation manners of the present invention, and their descriptions are relatively specific and detailed. However, it should not be understood as a limitation on the scope of the invention patent. It should be noted that for those of ordinary skill in the art, without departing from the concept of the present invention, several modifications and improvements can still be made, and these all belong to the protection scope of the present invention. Therefore, the protection scope of the present invention patent should be subject to the appended claims, and the description and drawings can be used to explain the content of the claims.

Claims

1. A solar cell, characterized in that, The solar cell includes a hole transport layer and a perovskite layer arranged in sequence; The hole transport layer includes a first hole transport film and a second hole transport film arranged in sequence, and the second hole transport film is disposed between the first hole transport film and the perovskite layer; The component of the first hole transport film includes a p-type semiconductor material, and the component of the second hole transport film includes an array material; The array material contains an array structure formed by nanorods. The nanorods include a rod core and a shell layer located on at least part of the surface of the rod core. The component of the rod core includes a p-type semiconductor material, and the component of the shell layer includes MoO3.

2. The solar cell according to claim 1, characterized in that, The length of the rod core is 30 nm to 100 nm.

3. The solar cell according to claim 1, characterized in that, The array material has a porous structure, and the aperture of at least part of the holes in the porous structure is 100 nm to 500 nm.

4. The solar cell according to claim 1, characterized in that, In the nanorod, the thickness of the shell layer is 10 nm to 50 nm.

5. The solar cell according to claim 4, wherein, The thickness of the shell layer is 10 nm to 40 nm.

6. The solar cell according to claim 5, wherein, The thickness of the shell layer is 15 nm to 30 nm.

7. The solar cell according to claim 1, characterized in that, The p-type semiconductor material is a p-type semiconductor oxide.

8. The solar cell according to claim 1, wherein The p-type semiconductor material includes at least one of nickel oxide, copper oxide, cuprous oxide, copper cyanide, and copper iodide.

9. The solar cell according to claim 1, wherein, The preparation method of the array material includes the following steps: Subjecting the precursor of the p-type semiconductor material to a first deposition treatment and then an annealing treatment to obtain the rod core; Performing a second deposition treatment on the surface of the rod core with the precursor of MoO3 to form the shell layer, thereby obtaining the array material.

10. The solar cell according to claim 9, characterized in that, The thickness of the second hole transport film is 30 nm to 120 nm.

11. The solar cell according to claim 10, characterized in that, The thickness of the second hole transport film is 30 nm to 100 nm.

12. The solar cell according to claim 1, wherein, The first hole transport film satisfies at least one of the following characteristics (a) to (c): (a) The thickness of the first hole transport film is 20 nm to 50 nm; (b) The p-type semiconductor material in the first hole transport film includes at least one of nickel oxide, copper oxide, cuprous oxide, copper cyanide, and copper iodide; (c) The p-type semiconductor material in the first hole transport film is the same as the p-type semiconductor material in the array material.

13. The solar cell according to claim 12, characterized in that, The thickness of the first hole transport film is 20 nm to 40 nm.

14. The solar cell according to claim 1, wherein, The perovskite layer satisfies at least one of the following characteristics (e) to (f): (e) The band gap of the perovskite layer is 1.20 eV to 2.30 eV; (f) The thickness of the perovskite layer is 400 nm to 1000 nm.

15. A photovoltaic module, characterized in that, A solar cell comprising the solar cell according to any one of claims 1 to 14.

16. A photovoltaic system, characterized in that, A photovoltaic module comprising the photovoltaic module according to claim 15.

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