Hole transport layer and preparation method and application thereof

Abstract

The invention provides a hole transport layer and a preparation method and application thereof, the hole transport layer comprises a nickel oxide film, a mixed oxide film and an aluminum oxide film which are sequentially stacked, the mixed oxide film comprises nickel oxide layers and aluminum oxide layers, and the nickel oxide layers and the aluminum oxide layers are alternately stacked. Compared with a traditional hole transport layer, the hole transport layer has the advantages that the light absorption is obviously reduced, the light loss is reduced, the conductivity of a NiOx film is improved, the grain boundary defect of NiOx can be passivated, the non-radiative recombination is reduced, and the photoelectric property of a device is improved.

Description

Technical Field

[0001] This invention belongs to the field of battery materials technology, and relates to a hole transport layer, its preparation method and application. Background Technology

[0002] Metal oxides (MOs) are widely used in perovskite photovoltaic manufacturing due to their high carrier mobility, low production cost, excellent material stability, scalability, and reproducibility. However, considering the high reactivity of organic cations, MOs may cause perovskite decomposition due to undercoordinated atoms and dangling bonds on the MOs surface. For p-type MOs, nickel oxide (NiOx) is widely used as the hole transport material. x Ni≥3+ sites on the surface can lead to cation deprotonation and iodide oxidation at high temperatures. MOs exhibit varying degrees of reactivity at the perovskite interface, which can generate interface defects and ultimately reduce device efficiency and lifetime.

[0003] To date, a significant amount of research has focused on reducing defects at the MO / perovskite interface. For example, various organic interlayers, such as Lewis acid-base organic salts, dye molecules, and self-assembled monolayers, have been developed to passivate interface defects. However, these organic interlayers need to be very thin (several to tens of nanometers), typically deposited via spin coating, which is unscalable and difficult for large-area fabrication. Furthermore, the fabricated cells must guarantee a long lifespan, requiring a sufficiently stable passivation process to withstand various stress factors during long-term operation. These developments necessitate the advancement of efficient, industrially compatible, and long-term stable contact interface passivation.

[0004] CN109980094A discloses a method for preparing a NiO hole transport layer for a perovskite solar cell. The method involves taking nano-NiO and 5-20 parts of micron-sized NiO, ultrasonically dispersing the nano-NiO and micron-sized NiO separately until uniform, then dispersing the nano-NiO dispersion and the NiO dispersion together until uniform. The solvent is removed, and the uniformly dispersed NiO particles are thoroughly mixed with polyvinyl alcohol to prepare a NiO coating. The NiO coating is then applied to the perovskite light-absorbing layer of the perovskite solar cell using a blade coating method. After the coating is cured, the NiO hole transport layer is obtained.

[0005] CN115094458A discloses a Cu-doped NiO hole transport layer thin film, its preparation method, and its application. The preparation method is as follows: a nickel-copper composite film is deposited by electron beam evaporation, and then the nickel-copper composite film is calcined in an air atmosphere to obtain a Cu-doped NiO hole transport layer thin film; wherein, nickel and copper are deposited simultaneously during the electron beam evaporation deposition process, and a cold cathode ion beam is used for assisted deposition during the deposition process.

[0006] In the hole transport layer described above, the low conductivity of nickel oxide itself causes holes to accumulate at the interface, which increases carrier recombination and leads to a decrease in the photoelectric performance of the optical device. Summary of the Invention

[0007] The purpose of this invention is to provide a hole transport layer, its preparation method, and its application. Compared to traditional hole transport layers, the hole transport layer of this invention significantly reduces light absorption, thereby reducing light loss and improving the performance of NiO. x The electrical conductivity of the thin film can also passivate NiO. x Grain boundary defects can reduce nonradiative recombination and improve the optoelectronic performance of devices.

[0008] In order to achieve the purpose of the invention, the present invention adopts the following technical solutions:

[0009] In a first aspect, the present invention provides a hole transport layer comprising a nickel oxide film, a mixed oxide film and an aluminum oxide film stacked sequentially, wherein the mixed oxide film comprises a nickel oxide layer and an aluminum oxide layer, and the nickel oxide layer and the aluminum oxide layer are stacked alternately.

[0010] Nickel oxide (NiO) x The low conductivity of NiO₂ itself leads to hole accumulation at the interface, increasing carrier recombination. This invention incorporates a mixed oxide layer composed of alternating layers of nickel oxide and aluminum oxide between the nickel oxide and aluminum oxide films. This helps reduce light absorption and loss in the film, improving the light efficiency of NiO₂. x The electrical conductivity of the thin film can also passivate NiO. x Grain boundary defects, and aluminum oxide (AlO) x The negative fixed charge characteristic of NiO x Inserting it into the perovskite interface can also effectively change the proportion of carriers far from the trapping section on the interface, reduce nonradiative recombination, and improve the optoelectronic performance of the device.

[0011] Preferably, the thickness of the nickel oxide film is 10-16 nm, for example: 10 nm, 12 nm, 14 nm, 15 nm or 16 nm, etc., and is not limited to the listed values. Other unlisted values ​​within this range are also applicable.

[0012] Preferably, the thickness of the mixed oxide film is 10-20 nm, for example: 10 nm, 12 nm, 15 nm, 18 nm or 20 nm, etc., and is not limited to the listed values. Other unlisted values ​​within this range are also applicable.

[0013] Preferably, the thickness of the aluminum oxide film is 0.1 to 5 nm, for example: 0.1 nm, 0.5 nm, 1 nm, 2 nm or 5 nm, etc., and is not limited to the listed values. Other unlisted values ​​within this range are also applicable.

[0014] Preferably, the thickness of the nickel oxide layer is 0.2 to 1 nm, for example: 0.2 nm, 0.4 nm, 0.5 nm, 0.8 nm or 1 nm, etc., and is not limited to the listed values. Other unlisted values ​​within this range are also applicable.

[0015] Preferably, the thickness of the aluminum oxide layer is 0.3 to 2 nm, for example: 0.3 nm, 0.8 nm, 1 nm, 1.5 nm or 2 nm, etc., and is not limited to the listed values. Other unlisted values ​​within this range are also applicable.

[0016] Preferably, the total thickness ratio of the nickel oxide layer and the aluminum oxide layer in the mixed oxide film is 1:(0.5 to 1.5), for example: 1:0.5, 1:0.8, 1:1, 1:1.2 or 1:1.5, etc., and is not limited to the listed values. Other unlisted values ​​within this range are also applicable.

[0017] In a second aspect, the present invention provides a method for preparing a hole transport layer as described in the first aspect, the method comprising the following steps:

[0018] (1) The substrate is placed in an atomic layer deposition apparatus and nickel oxide deposition is performed to obtain a nickel oxide film;

[0019] (2) A mixed oxide film is obtained by alternating deposition of nickel oxide and aluminum oxide on the surface of the nickel oxide film;

[0020] (3) Aluminum oxide deposition is performed on the surface of the mixed oxide film to obtain the hole transport layer.

[0021] This invention employs atomic layer deposition (ALD) to prepare a hole transport layer. After depositing a nickel oxide film of a certain thickness, nickel oxide and aluminum oxide layers are deposited alternately to a certain thickness, and finally a thin aluminum oxide layer is deposited. This method is beneficial for reducing light absorption and light loss in the film, improving the conductivity of the nickel oxide film, passivating grain boundary defects in nickel oxide, reducing non-radiative recombination, and improving the optoelectronic performance of the device.

[0022] Preferably, the substrate in step (1) includes an ITO conductive glass substrate and / or a crystalline silicon battery substrate with an ITO composite layer.

[0023] Preferably, step (1) involves placing the substrate in front of an atomic layer deposition apparatus for ultrasonic treatment, drying, and ultraviolet ozone treatment.

[0024] Preferably, the ultrasonic fluid used in the ultrasound includes any one or a combination of at least two of glass cleaner, deionized water, ethanol, acetone, isopropanol, or ethanol. Typical but non-limiting combinations include combinations of glass cleaner and deionized water, glass cleaner, deionized water and ethanol, or ethanol and isopropanol.

[0025] Preferably, the sonication time for each ultrasonic fluid is 10 to 20 minutes, for example: 10 minutes, 12 minutes, 15 minutes, 18 minutes or 20 minutes, etc., not limited to the listed values, and other unlisted values ​​within this range are also applicable.

[0026] Preferably, the ultraviolet ozone treatment time is 10 to 30 minutes, for example: 10 minutes, 15 minutes, 20 minutes, 25 minutes or 30 minutes, etc., and is not limited to the listed values. Other unlisted values ​​within this range are also applicable.

[0027] Preferably, the nickel oxide deposition process in step (1) includes:

[0028] After introducing a nickel source into the atomic layer deposition apparatus, inert gas is purged, followed by inert gas purging after introducing an oxygen source. This process is repeated to obtain a nickel oxide film.

[0029] Preferably, the temperature of the atomic layer deposition apparatus is 120–180°C, for example: 120°C, 130°C, 150°C, 160°C, or 180°C, etc., and is not limited to the listed values. Other unlisted values ​​within this range are also applicable.

[0030] Preferably, the nickel source is introduced for a period of 0.01 to 0.03 s, for example: 0.01 s, 0.015 s, 0.02 s, 0.025 s or 0.03 s, etc., and is not limited to the listed values. Other unlisted values ​​within this range are also applicable.

[0031] Preferably, the nickel source comprises nickel dicerocene.

[0032] Preferably, the inert gas purging time after the nickel source is introduced is 1 to 2 seconds, for example: 1 second, 1.2 seconds, 1.5 seconds, 1.8 seconds or 2 seconds, etc., and is not limited to the listed values. Other unlisted values ​​within this range are also applicable.

[0033] Preferably, the oxygen source is introduced for 0.5 to 1.5 seconds, for example, 0.5 seconds, 0.8 seconds, 1 second, 1.2 seconds, or 1.5 seconds, etc., and is not limited to the listed values. Other unlisted values ​​within this range are also applicable.

[0034] Preferably, the oxygen source includes ozone.

[0035] Preferably, the time for purging with inert gas after introducing the oxygen source is 3 to 8 seconds, for example: 3 seconds, 4 seconds, 5 seconds, 6 seconds or 8 seconds, etc., not limited to the listed values, and other unlisted values ​​within this range are also applicable.

[0036] Preferably, the deposition rate of the nickel oxide deposition process is 0.2 to 1 nm / cycle, for example: 0.2 nm / cycle, 0.4 nm / cycle, 0.5 nm / cycle, 0.8 nm / cycle or 1 nm / cycle, etc., and is not limited to the listed values. Other unlisted values ​​within this range are also applicable.

[0037] Preferably, the alternating deposition of nickel oxide and aluminum oxide in step (2) includes:

[0038] After introducing an aluminum source into the atomic layer deposition apparatus, inert gas purging is performed. Then, after introducing a first oxygen source, inert gas purging is performed. After introducing a nickel source, inert gas purging is performed. After introducing a second oxygen source, inert gas purging is performed. This process is repeated to obtain a mixed oxide film.

[0039] The alternating deposition process described in this invention requires first depositing an aluminum oxide layer. The deposition speed and number of cycles are set according to the required thickness of the aluminum oxide and nickel oxide layers. For example, two aluminum oxide cycles and one nickel oxide cycle can be used as one large cycle. One large cycle yields a mixed oxide film with a thickness of 1 nm. After 15 large cycles, a mixed oxide film with a thickness of 15 nm is obtained.

[0040] Preferably, the temperature of the atomic layer deposition apparatus is 155–165°C, for example: 155°C, 158°C, 160°C, 162°C, or 165°C, etc., and is not limited to the listed values. Other unlisted values ​​within this range are also applicable.

[0041] Preferably, the time for introducing the aluminum source is 0.06 to 0.12 s, for example: 0.06 s, 0.08 s, 0.1 s, 0.11 s or 0.12 s, etc., and is not limited to the listed values. Other unlisted values ​​within this range are also applicable.

[0042] Preferably, the aluminum source includes trimethylaluminum.

[0043] Preferably, the time for purging with inert gas after introducing the aluminum source is 1 to 2 seconds, for example: 1 second, 1.2 seconds, 1.5 seconds, 1.8 seconds or 2 seconds, etc., and is not limited to the listed values. Other unlisted values ​​within this range are also applicable.

[0044] Preferably, the time for introducing the first oxygen source is 0.1 to 0.2 ms, for example: 0.1s, 0.12s, 0.15s, 0.18s or 0.2s, etc., and is not limited to the listed values. Other unlisted values ​​within this range are also applicable.

[0045] Preferably, the first oxygen source includes ozone.

[0046] Preferably, the time for purging with inert gas after introducing the first oxygen source is 1 to 3 seconds, for example: 1 second, 1.5 seconds, 2 seconds, 2.5 seconds or 3 seconds, etc., and is not limited to the listed values. Other unlisted values ​​within this range are also applicable.

[0047] Preferably, the nickel source is introduced for a period of 0.01 to 0.03 s, for example: 0.01 s, 0.015 s, 0.02 s, 0.025 s or 0.03 s, etc., and is not limited to the listed values. Other unlisted values ​​within this range are also applicable.

[0048] Preferably, the nickel source comprises nickel dicerocene.

[0049] Preferably, the inert gas purging time after the nickel source is introduced is 1 to 2 seconds, for example: 1 second, 1.2 seconds, 1.5 seconds, 1.8 seconds or 2 seconds, etc., and is not limited to the listed values. Other unlisted values ​​within this range are also applicable.

[0050] Preferably, the time for introducing the second oxygen source is 0.5 to 1.5 s, for example: 0.5 s, 0.8 s, 1 s, 1.2 s or 1.5 s, etc., and is not limited to the listed values. Other unlisted values ​​within this range are also applicable.

[0051] Preferably, the second oxygen source includes ozone.

[0052] Preferably, the inert gas purging time after the second oxygen source is introduced is 3 to 8 seconds, for example: 3 seconds, 4 seconds, 5 seconds, 6 seconds or 8 seconds, etc., and is not limited to the listed values. Other unlisted values ​​within this range are also applicable.

[0053] Preferably, the deposition rate of the alternating deposition process is 0.1 to 1 nm / cycle, for example: 0.1 nm / cycle, 0.2 nm / cycle, 0.5 nm / cycle, 0.8 nm / cycle or 1 nm / cycle, etc., and is not limited to the listed values. Other unlisted values ​​within this range are also applicable.

[0054] Preferably, the aluminum oxide deposition process in step (3) includes:

[0055] An aluminum source is introduced into the atomic layer deposition apparatus, followed by inert gas purging. Then, an oxygen source is introduced, followed by inert gas purging. This process is repeated to obtain an aluminum oxide film.

[0056] Preferably, the temperature of the atomic layer deposition apparatus is 155–165°C, for example: 155°C, 158°C, 160°C, 162°C, or 165°C, etc., and is not limited to the listed values. Other unlisted values ​​within this range are also applicable.

[0057] Preferably, the time for introducing the aluminum source is 0.06 to 0.12 s, for example: 0.06 s, 0.08 s, 0.1 s, 0.11 s or 0.12 s, etc., and is not limited to the listed values. Other unlisted values ​​within this range are also applicable.

[0058] Preferably, the aluminum source includes trimethylaluminum.

[0059] Preferably, the time for purging with inert gas after introducing the aluminum source is 1 to 2 seconds, for example: 1 second, 1.2 seconds, 1.5 seconds, 1.8 seconds or 2 seconds, etc., and is not limited to the listed values. Other unlisted values ​​within this range are also applicable.

[0060] Preferably, the oxygen source is introduced for 0.1 to 0.2 ms, for example: 0.1s, 0.12s, 0.15s, 0.18s or 0.2s, etc., and is not limited to the listed values. Other unlisted values ​​within this range are also applicable.

[0061] Preferably, the oxygen source includes ozone.

[0062] Preferably, the time for purging with inert gas after introducing the oxygen source is 1 to 3 seconds, for example: 1 second, 1.5 seconds, 2 seconds, 2.5 seconds or 3 seconds, etc., and is not limited to the listed values. Other unlisted values ​​within this range are also applicable.

[0063] Preferably, the deposition rate of the aluminum oxide deposition process is 0.1 to 0.4 nm / cycle, for example: 0.1 nm / cycle, 0.15 nm / cycle, 0.2 nm / cycle, 0.3 nm / cycle or 0.4 nm / cycle, etc., and is not limited to the listed values. Other unlisted values ​​within this range are also applicable.

[0064] Thirdly, the present invention provides a perovskite solar cell comprising a hole transport layer as described in the first aspect.

[0065] The perovskite solar cells described in this invention include conventional perovskite solar cells and perovskite-silicon tandem solar cells containing perovskite solar cells.

[0066] Compared with the prior art, the present invention has the following beneficial effects:

[0067] (1) The performance parameters of perovskite solar cells and perovskite-silicon tandem solar cells fabricated using the hole transport layer described in this invention, such as open-circuit voltage, short-circuit current, and fill factor, are all improved, and the conversion efficiency is also improved accordingly. The open-circuit voltage shows the greatest improvement, indicating that the hole transport layer described in this invention significantly reduces light absorption compared to traditional hole transport layers, thereby reducing light loss and improving NiO efficiency. x The electrical conductivity of the thin film can also passivate NiO. x Grain boundary defects can reduce nonradiative recombination and improve the optoelectronic performance of devices.

[0068] (2) The hole transport layer described in this invention is used to fabricate perovskite solar cells with V OC It can reach above 1.18V, J SC Up to 20.11 mA / cm 2 The above results in a flyback efficiency (FF) of over 80.23% and a PCE of over 19.1%. Furthermore, the hole transport layer described in this invention is also applicable to perovskite-silicon tandem solar cells, enabling the fabrication of perovskite-silicon tandem solar cells with a V0. OC Up to 1.89V, J SC Up to 19.49 mA / cm 2 FF can reach 80.83%, and PCE can reach 29.77%. Attached Figure Description

[0069] Figure 1 This is a comparison chart of the stability of the hole transport layer prepared in Example 1 and Comparative Example 1 in the battery.

[0070] Figure 2 This is a comparison chart of the stability of the hole transport layer prepared in Example 8 and Comparative Example 2 in the battery. Detailed Implementation

[0071] The technical solution of the present invention is further described below by way of specific embodiments. It should be understood by those skilled in the art that the embodiments are merely to help understand the present invention and should not be regarded as specific limitations of the present invention.

[0072] Example 1

[0073] This embodiment provides a hole transport layer, which is fabricated by the following method:

[0074] (1) Using ITO conductive glass as the substrate, the substrate was ultrasonically treated with glass cleaner, deionized water, ethanol, acetone, isopropanol and ethanol for 15 min in sequence. The substrate was dried with dry air and then treated with ultraviolet-ozone for 20 min. The substrate was placed in an atomic layer deposition apparatus with the temperature controlled at 150℃. Nickel dicene was introduced for 0.02 s, argon was purged for 1.5 s, ozone was introduced for 1 s, and argon was purged for 5 s. The deposition rate was 0.5 nm / cycle. After 28 cycles, a nickel oxide film with a thickness of 14 nm was obtained.

[0075] (2) The temperature of the control device is 159℃. Trimethylaluminum is introduced for 0.09s, argon is purged for 1.5s, ozone is introduced for 0.15ms, argon is purged for 2s, and the deposition rate is 0.25nm / cycle (aluminum oxide cycle). Nickel dicerocene is introduced for 0.02s, argon is purged for 1.5s, ozone is introduced for 1s, argon is purged for 5s, and the deposition rate is 0.5nm / cycle (nickel oxide cycle). Two aluminum oxide cycles and one nickel oxide cycle constitute one large cycle (i.e., aluminum oxide cycle-nickel oxide cycle-aluminum oxide cycle). The deposition thickness of one large cycle is 1nm (the aluminum oxide layer thickness is 0.5nm and the nickel oxide layer thickness is 0.5nm). Repeat 15 large cycles to obtain a mixed oxide film with a thickness of 15nm.

[0076] (3) The temperature of the control device is 159℃, trimethylaluminum is introduced for 0.09s, argon is purged for 1.5s, ozone is introduced for 0.15ms, argon is purged for 2s, the deposition rate is 0.25nm / cycle, and the aluminum oxide film thickness is 1nm after 4 cycles to obtain the hole transport layer.

[0077] Example 2

[0078] This embodiment provides a hole transport layer, which is fabricated by the following method:

[0079] (1) Using ITO conductive glass as the substrate, the substrate was ultrasonically treated with glass cleaner, deionized water, ethanol, acetone, isopropanol and ethanol for 10 min in sequence. The substrate was dried with dry air and then treated with ultraviolet-ozone for 10 min. The substrate was placed in an atomic layer deposition apparatus with the temperature controlled at 120℃. Nickel dicene was introduced for 0.01 s, argon was purged for 1 s, ozone was introduced for 0.5 s, argon was purged for 3 s, and the deposition rate was 0.5 nm / cycle. After 26 cycles, a nickel oxide film with a thickness of 13 nm was obtained.

[0080] (2) The temperature of the control device is 155℃. Trimethylaluminum is introduced for 0.06s, argon is purged for 1s, ozone is introduced for 0.1ms, argon is purged for 1s, the deposition rate is 0.25nm / cycle (aluminum oxide cycle), nickel dicerocene is introduced for 0.01s, argon is purged for 1s, ozone is introduced for 0.5s, argon is purged for 3s, the deposition rate is 0.5nm / cycle (nickel oxide cycle). Two aluminum oxide cycles and one nickel oxide cycle constitute one large cycle (i.e., aluminum oxide cycle-nickel oxide cycle-aluminum oxide cycle). The deposition thickness of two large cycles is 2nm (the thickness of the aluminum oxide layer is 1nm, and the thickness of the nickel oxide layer is 1nm). The large cycles are repeated for 15 times to obtain a mixed oxide film with a thickness of 15nm.

[0081] (3) The temperature of the control device is 155℃, trimethylaluminum is introduced for 0.06s, argon is purged for 1s, ozone is introduced for 0.1ms, argon is purged for 1s, the deposition rate is 0.25nm / cycle, the aluminum oxide film thickness is 1nm after 4 cycles, and the hole transport layer is obtained.

[0082] Example 3

[0083] This embodiment provides a hole transport layer, which is fabricated by the following method:

[0084] (1) Using ITO conductive glass as the substrate, the substrate was ultrasonically treated with glass cleaner, deionized water, ethanol, acetone, isopropanol and ethanol for 3 min in sequence. The substrate was dried with dry air and then treated with ultraviolet-ozone for 30 min. The substrate was placed in an atomic layer deposition apparatus with the temperature controlled at 180℃. Diocene nickel was introduced for 0.03 s, argon was purged for 3 s, ozone was introduced for 1.5 s, argon was purged for 8 s, and the deposition rate was 0.5 nm / cycle. After 24 cycles, a nickel oxide film with a thickness of 12 nm was obtained.

[0085] (2) The temperature of the control device is 165℃. Trimethylaluminum is introduced for 0.12s, argon is purged for 3s, ozone is introduced for 0.3ms, argon is purged for 3s, the deposition rate is 0.25nm / cycle (aluminum oxide cycle), nickel dicerocene is introduced for 0.03s, argon is purged for 3s, ozone is introduced for 1.5s, argon is purged for 8s, the deposition rate is 0.5nm / cycle (nickel oxide cycle). Two aluminum oxide cycles and one nickel oxide cycle constitute one large cycle (i.e., aluminum oxide cycle-nickel oxide cycle-aluminum oxide cycle). Three large cycles are deposited to a deposition thickness of 3nm (aluminum oxide layer thickness is 1.5nm, nickel oxide layer thickness is 1.5nm). The large cycles are repeated for 15 cycles to obtain a mixed oxide film with a thickness of 15nm.

[0086] (3) The temperature of the control device is 165℃, trimethylaluminum is introduced for 0.12s, argon is purged for 3s, ozone is introduced for 0.3ms, argon is purged for 3s, the deposition rate is 0.25nm / cycle, and the aluminum oxide film thickness is 1nm after 4 cycles to obtain the hole transport layer.

[0087] Example 4

[0088] The only difference between this embodiment and Embodiment 1 is that the total thickness ratio of the nickel oxide layer and the aluminum oxide layer in the mixed oxide film is 1:0.5. All other conditions and parameters are exactly the same as in Embodiment 1.

[0089] Example 5

[0090] The only difference between this embodiment and Embodiment 1 is that the total thickness ratio of the nickel oxide layer and the aluminum oxide layer in the mixed oxide film is 1:1.5. All other conditions and parameters are exactly the same as in Embodiment 1.

[0091] Example 6

[0092] The only difference between this embodiment and Embodiment 1 is that the total thickness ratio of the nickel oxide layer and the aluminum oxide layer in the mixed oxide film is 1:0.2. All other conditions and parameters are exactly the same as in Embodiment 1.

[0093] Example 7

[0094] The only difference between this embodiment and Embodiment 1 is that the total thickness ratio of the nickel oxide layer and the aluminum oxide layer in the mixed oxide film is 1:2. All other conditions and parameters are exactly the same as in Embodiment 1.

[0095] Example 8

[0096] The only difference between this embodiment and Embodiment 1 is that a semi-finished heterojunction cell is used as the crystalline silicon base cell, and the ITO conductive glass in Embodiment 1 is replaced with a 30nm thick ITO composite layer sputtered on the N-side microcrystalline silicon of the crystalline silicon cell substrate using PVD. All other conditions and parameters are exactly the same as in Embodiment 1.

[0097] Comparative Example 1

[0098] In this comparative example, an atomic layer deposition (ALD) method was used to deposit a nickel oxide hole transport layer on ITO glass. Nickel-cerocenium and ozone were used as precursors for nickel and oxygen, respectively. Argon was used as the carrier gas and purging gas. The nickel source storage temperature was set to 120°C. Each deposition cycle consisted of four steps: introducing nickel-cerocenium reactants for 0.02 s, purging with argon for 1.5 s, introducing ozone for 1 s, and purging with argon for 5 s. During the deposition process, the reaction chamber temperature was controlled at 150°C, the nickel oxide deposition rate was 0.5 nm / cycle, and 30 cycles were performed to achieve a thickness of 15 nm.

[0099] Comparative Example 2

[0100] The only difference between this comparative example and Comparative Example 1 is that the ITO conductive glass is replaced with a 30nm thick ITO composite layer sputtered on the N-side microcrystalline silicon of the crystalline silicon battery substrate using PVD. All other conditions and parameters are exactly the same as those in Comparative Example 1.

[0101] Performance testing:

[0102] Lead iodide, cesium iodide, and lead bromide were deposited onto the hole transport layers prepared in Examples 1-8 and Comparative Examples 1-2 using co-evaporation deposition technology, respectively. The deposition rate of lead iodide was [missing information]. The evaporation rate of cesium lead iodide is The lead bromide evaporation rate is The thickness is 350-600 nm. Then, a mixed organic liquid containing methyl iodide, methyl bromide, methyl iodide, and methyl chloroamine dissolved in isopropanol is spin-coated onto the evaporated film at a concentration between 1.0-1.5 M, and annealed at 100-150℃ for 10-15 min to prepare a perovskite light-absorbing layer. A C60 electron transport layer with a thickness of 20 nm is then prepared on the perovskite light-absorbing layer obtained in the previous step by evaporation. Using atomic deposition, a tin dioxide thin film with a thickness of 15 nm is prepared on top of the C60 electron transport layer. A silver metal electrode with a thickness of 120 nm is then deposited on the tin dioxide surface to obtain a perovskite solar cell (or a perovskite-silicon tandem solar cell). The performance test results are shown in Table 1.

[0103] Table 1

[0104]

[0105]

[0106] As can be seen from Table 1, based on Examples 1-3 and Example 8, the perovskite solar cell fabricated using the hole transport layer described in this invention exhibits V3. OC It can reach above 1.18V, J SC Up to 20.11 mA / cm 2 The above results in a flyback efficiency (FF) of over 80.23% and a PCE of over 19.1%. Furthermore, the hole transport layer described in this invention is also applicable to perovskite-silicon tandem solar cells, enabling the fabrication of perovskite-silicon tandem solar cells with a V0. OC Up to 1.89V, J SC Up to 19.49 mA / cm 2 FF can reach 80.83%, and PCE can reach 29.77%.

[0107] A comparison of Examples 1 and 4-7 shows that the total thickness ratio of the nickel oxide layer to the aluminum oxide layer in the hybrid oxide film of the hole transport layer of the present invention affects its performance. Controlling the total thickness ratio of the nickel oxide layer to the aluminum oxide layer in the hybrid oxide film to 1:0.5-1.5 results in a hole transport layer with better performance. If the proportion of the nickel oxide layer is too high, the AlO2... x The negative fixed charge characteristics will decrease, which will relatively reduce the proportion of carriers far from the capture section on the interface, and the reduction of recombination loss will also be relatively reduced, resulting in a decrease in device performance; if the proportion of aluminum oxide layer is too high, the conductivity will deteriorate, and the device performance will decrease.

[0108] The stability comparison diagram of the hole transport layer prepared in Example 1 and Comparative Example 1 in the battery is shown in the figure below. Figure 1 As shown in the figure, the stability comparison of the hole transport layer prepared in Example 8 and Comparative Example 2 in the battery is shown in the figure. Figure 2 As shown, a comparison between Example 1 and Comparative Example 1, and between Example 8 and Comparative Example 2, reveals that the perovskite solar cells and perovskite-silicon tandem solar cells fabricated using the hole transport layer described in this invention exhibit improved performance parameters such as open-circuit voltage, short-circuit current, and fill factor. Consequently, the conversion efficiency is also improved, with the open-circuit voltage showing the greatest increase. This indicates that the hole transport layer described in this invention significantly reduces light absorption compared to traditional hole transport layers, thereby reducing light loss and improving NiO efficiency. x The electrical conductivity of the thin film can also passivate NiO. x Grain boundary defects can reduce nonradiative recombination and improve the optoelectronic performance of devices.

[0109] The applicant declares that the above is only a specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Those skilled in the art should understand that any changes or substitutions that can be easily thought of by those skilled in the art within the technical scope disclosed by the present invention fall within the scope of protection and disclosure of the present invention.

Claims

1. A hole transport layer, characterized in that, The hole transport layer includes a nickel oxide film, a mixed oxide film, and an aluminum oxide film stacked sequentially. The mixed oxide film includes a nickel oxide layer and an aluminum oxide layer, which are stacked alternately.

2. The hole transport layer as described in claim 1, characterized in that, The thickness of the nickel oxide film is 10–16 nm; Preferably, the thickness of the mixed oxide film is 10–20 nm; Preferably, the thickness of the aluminum oxide film is 0.1 to 5 nm.

3. The hole transport layer as described in claim 1 or 2, characterized in that, The thickness of the nickel oxide layer is 0.2–1 nm; Preferably, the thickness of the aluminum oxide layer is 0.3–2 nm; Preferably, the total thickness ratio of the nickel oxide layer and the aluminum oxide layer in the mixed oxide film is 1:(0.5 to 1.5).

4. A method for preparing a hole transport layer as described in any one of claims 1-3, characterized in that, The preparation method includes the following steps: (1) The substrate is placed in an atomic layer deposition apparatus and nickel oxide deposition is performed to obtain a nickel oxide film; (2) A mixed oxide film is obtained by alternating deposition of nickel oxide and aluminum oxide on the surface of the nickel oxide film; (3) Aluminum oxide deposition is performed on the surface of the mixed oxide film to obtain the hole transport layer.

5. The preparation method according to claim 4, characterized in that, The substrate in step (1) includes an ITO conductive glass substrate and / or a crystalline silicon battery substrate with an ITO composite layer; Preferably, step (1) involves placing the substrate in front of the atomic layer deposition apparatus for ultrasonic treatment, drying, and ultraviolet ozone treatment; Preferably, the ultrasonic fluid used in the ultrasound includes any one or a combination of at least two of glass cleaner, deionized water, ethanol, acetone, isopropanol, or ethanol. Preferably, the ultrasonic time for each ultrasonic fluid is 10–20 min; Preferably, the ultraviolet ozone treatment time is 10 to 30 minutes.

6. The preparation method according to claim 4 or 5, characterized in that, Step (1) of the nickel oxide deposition process includes: After introducing a nickel source into the atomic layer deposition apparatus, inert gas purging is performed. After introducing an oxygen source, inert gas purging is performed. This cycle is repeated to obtain a nickel oxide film. Preferably, the temperature of the atomic layer deposition apparatus is 120–180°C; Preferably, the nickel source is introduced for 0.01 to 0.03 seconds; Preferably, the nickel source comprises nickel dicero; Preferably, the inert gas purging time after the nickel source is introduced is 1 to 2 seconds; Preferably, the oxygen source is introduced for 0.5 to 1.5 seconds; Preferably, the oxygen source includes ozone; Preferably, the inert gas purging time after the oxygen source is introduced is 3 to 8 seconds; Preferably, the deposition rate of the nickel oxide deposition treatment is 0.2 to 1 nm / cycle.

7. The preparation method according to any one of claims 4-6, characterized in that, Step (2) of the alternating deposition of nickel oxide and aluminum oxide includes: After introducing an aluminum source into the atomic layer deposition apparatus, inert gas purging is performed. After introducing a first oxygen source, inert gas purging is performed. After introducing a nickel source, inert gas purging is performed. After introducing a second oxygen source, inert gas purging is performed. This process is repeated to obtain a mixed oxide film. Preferably, the temperature of the atomic layer deposition apparatus is 155–165°C; Preferably, the time for introducing the aluminum source is 0.06 to 0.12 seconds; Preferably, the aluminum source comprises trimethylaluminum; Preferably, the inert gas purging time after the aluminum source is introduced is 1 to 2 seconds; Preferably, the time for introducing the first oxygen source is 0.1–0.2 ms; Preferably, the first oxygen source includes ozone; Preferably, the inert gas purging time after the first oxygen source is introduced is 1 to 3 seconds.

8. The preparation method according to claim 7, characterized in that, The nickel source is introduced for a period of 0.01 to 0.03 seconds. Preferably, the nickel source comprises nickel dicero; Preferably, the inert gas purging time after the nickel source is introduced is 1 to 2 seconds; Preferably, the time for introducing the second oxygen source is 0.5 to 1.5 seconds; Preferably, the second oxygen source includes ozone; Preferably, the inert gas purging time after the second oxygen source is introduced is 3 to 8 seconds; Preferably, the deposition rate of the alternating deposition process is 0.1 to 1 nm / cycle.

9. The preparation method according to any one of claims 4-8, characterized in that, Step (3) of the aluminum oxide deposition process includes: An aluminum source is introduced into the atomic layer deposition apparatus and then purged with an inert gas. An oxygen source is introduced and then purged with an inert gas. This process is repeated to obtain an aluminum oxide film. Preferably, the temperature of the atomic layer deposition apparatus is 155–165°C; Preferably, the time for introducing the aluminum source is 0.06 to 0.12 seconds; Preferably, the aluminum source comprises trimethylaluminum; Preferably, the inert gas purging time after the aluminum source is introduced is 1 to 2 seconds; Preferably, the oxygen source is introduced for 0.1–0.2 ms; Preferably, the oxygen source includes ozone; Preferably, the inert gas purging time after the oxygen source is introduced is 1 to 3 seconds; Preferably, the deposition rate of the aluminum oxide deposition process is 0.1 to 0.4 nm / cycle.

10. A perovskite solar cell, characterized in that, The perovskite solar cell includes a hole transport layer as described in any one of claims 1-3.

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