A semi-transparent perovskite cell and a preparation method thereof

Abstract

This invention belongs to the field of solar cell technology, specifically relating to a semi-transparent perovskite solar cell and its fabrication method. The semi-transparent perovskite solar cell provided by this invention features a polyethyleneimine protective layer of a specific composition between the ITO electrode and the cathode transport layer. This protective layer exhibits excellent impact resistance, effectively buffering particle impacts during sputtering, while not affecting electron / hole transport or increasing the energy level barrier between the electrode and the perovskite layer. This is because the abundant amine groups in the polyethyleneimine protective layer material of this specific composition can form an interfacial dipole with the electrode, significantly reducing the work function of the cathode, which is beneficial for improving the open-circuit voltage of the device. The fill factor is also greatly improved, enabling the device to achieve ideal photoelectric conversion efficiency, ultimately contributing to the successful fabrication of high-performance semi-transparent devices.

Description

Technical Field

[0001] This invention belongs to the field of solar cell technology, specifically relating to a semi-transparent perovskite solar cell and its preparation method. Background Technology

[0002] Perovskite solar cells have garnered widespread attention due to their excellent photoelectric conversion efficiency and solution-processability. Currently, crystalline silicon solar cells in the photovoltaic market have reached a mature and stable level in terms of technology and processes. However, as improving the efficiency of single-junction cells becomes increasingly difficult, researchers are inclined to combine narrow-bandgap crystalline silicon cells with wide-bandgap perovskite solar cells to fabricate two-terminal perovskite / crystalline silicon tandem solar cells or four-terminal tandem devices. Sunlight enters from the wide-bandgap perovskite device end and reaches the silicon cell, fully utilizing different wavelengths of sunlight to achieve higher photon utilization. This necessitates the fabrication of high-efficiency semi-transparent perovskite solar cells with transparent top electrodes. Furthermore, semi-transparent perovskite cells can themselves serve as photovoltaic windows, offering significant advantages in fields such as building-integrated photovoltaics (BIPV).

[0003] The transparent top electrode required for fabricating semi-transparent perovskite solar cells must possess excellent photoelectric properties and stability, as well as superior optical transmittance. Transparent conductive oxide (ITO) is an excellent choice that meets these requirements; however, it is often fabricated using sputtering, where high-energy particle impacts can easily damage the underlying cathode transport layer and even the perovskite layer, making it difficult to achieve ideal device efficiency.

[0004] Therefore, when fabricating ITO top electrodes, in addition to optimizing the electrode sputtering process, we also need to introduce a suitable protective layer to reduce damage during sputtering. For example, some studies have used solution spin coating to prepare protective layers, but their impact resistance is generally poor, and there may be problems with insufficient energy level matching or insufficient electron transport performance, increasing the energy level barrier between the electrode and the perovskite layer, resulting in less than ideal device performance. Another approach is to first deposit a layer of SnO2 with good electron transport capabilities as a buffer through atomic layer deposition to fabricate highly efficient semi-transparent devices; however, this method requires expensive equipment, increasing costs. Summary of the Invention

[0005] Therefore, the technical problem to be solved by the present invention is to overcome the shortcomings of the protective layer in the prior art, which is not ideal and may also increase the energy level barrier between the electrode and the perovskite layer, affecting the electrical performance of the battery or causing the equipment to be expensive and costly. Thus, the present invention provides a semi-transparent perovskite battery and its preparation method.

[0006] Therefore, the present invention provides the following technical solution:

[0007] This invention provides a semi-transparent perovskite solar cell, comprising, from bottom to top, a substrate, a transparent conductive glass anode, an anode transport layer, a perovskite layer, a cathode transport layer, a polyethyleneimine protective layer, and an ITO electrode.

[0008] The polyethyleneimine has an average molecular weight of 1200-20000 and has the following structure:

[0009]

[0010] Optionally, the transparent conductive glass anode is at least one of FTO and ITO;

[0011] And / or, the thickness of the transparent conductive glass anode is 100-200 nm.

[0012] Optionally, the anode transport layer is at least one of PEDOT:PSS (poly(3,4-ethylenedioxythiophene / polystyrene sulfonate), PTAA (poly[bis(4-phenyl)(2,4,6-trimethylphenyl)amine]), and 2PACz ([2-(9H-carbazole-9-yl)ethyl]phosphonic acid);

[0013] And / or, the thickness of the anode transport layer is 0.8-30 nm.

[0014] Optionally, the perovskite layer has the composition ABX3; wherein A is CH3NH3. + HC(NH2)2 + Cs + One or more of them, where B is Pb 2+ Sn 2+ Cu 2+ One or more of them, where X is I - ,Br - Cl - One or more of the following;

[0015] And / or, the thickness of the perovskite layer is 300-450 nm.

[0016] Optionally, the cathode transport layer is C 60 (Carbon 60), PC 61 At least one of BM ([6,6]-phenyl C61 butyrate methyl ester), ZnO (zinc oxide), and TIPD (titanium acetylacetonate);

[0017] And / or, the thickness of the cathode transport layer is 5-20 nm.

[0018] Optionally, the thickness of the polyethyleneimine protective layer is 1-5 nm.

[0019] Optionally, the thickness of the ITO electrode is 100-300 nm.

[0020] The present invention also provides a method for preparing the above-mentioned semi-transparent perovskite solar cell, comprising the following steps:

[0021] S1, Obtain a substrate containing a transparent conductive glass anode, pre-treat it, and sequentially prepare an anode transport layer, a perovskite layer and a cathode transport layer;

[0022] S2, a polyethyleneimine protective layer is prepared on the cathode transport layer by spin coating;

[0023] S3 uses vacuum sputtering to deposit ITO electrodes.

[0024] Optionally, in step S3, the vacuum sputtering conditions are: sputtering power 70-100W, sputtering time 30-60min, argon flow rate 40-70sccm, and working pressure 0.5-5Pa.

[0025] Optionally, in step S2, the method for preparing the polyethyleneimine protective layer includes:

[0026] Polyethyleneimine was dissolved in an organic solvent, spin-coated, and annealed to obtain the polyethyleneimine protective layer.

[0027] Typically, and not limitingly, the methods for preparing each functional layer in the semi-transparent perovskite solar cell provided by this invention are all conventional in the field. For example:

[0028] The substrate containing the transparent conductive glass anode is commercially available. Pretreatment of the substrate includes ultrasonic cleaning of the transparent conductive glass substrate in at least one of the following solvents for 15-30 minutes: detergent, water, deionized water, acetone, and isopropanol. The cleaned substrate is then dried in an oven at 100-150°C for 3-5 minutes, followed by UVO treatment for 15-20 minutes.

[0029] The technical solution of this invention has the following advantages:

[0030] The semi-transparent perovskite solar cell provided by this invention features a polyethyleneimine protective layer of a specific composition between the ITO electrode and the cathode transport layer. This protective layer exhibits excellent impact resistance, effectively buffering particle impacts during sputtering, while not affecting electron / hole transport or increasing the energy level barrier between the electrode and the perovskite layer. This is because the abundant amine groups in the polyethyleneimine protective layer material of this specific composition can form an interfacial dipole with the electrode, significantly reducing the work function of the cathode, which is beneficial for improving the open-circuit voltage of the device. The fill factor is also greatly improved, enabling the device to achieve ideal photoelectric conversion efficiency, ultimately contributing to the successful fabrication of high-performance semi-transparent devices.

[0031] The method for preparing a semi-transparent perovskite solar cell provided by the present invention prepares a polyethyleneimine protective layer by spin coating before sputtering the ITO electrode, which can effectively buffer the particle impact during sputtering and improve the device performance.

[0032] The method for preparing a semi-transparent perovskite solar cell provided by the present invention can further reduce particle impact during sputtering by limiting the sputtering conditions. Attached Figure Description

[0033] To more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0034] Figure 1 This is a schematic diagram of the structure of the semi-transparent perovskite solar cell provided in the embodiments of the present invention;

[0035] Figure 2 This is a graph showing the current density versus voltage (JV) curves of the semi-transparent perovskite solar cell provided in Embodiment 1 of the present invention under illumination with an intensity of 100 milliwatts per square centimeter.

[0036] Figure 3 This is a graph showing the current density versus voltage (JV) curves of the semi-transparent perovskite solar cell provided in Embodiment 2 of the present invention under illumination with an intensity of 100 milliwatts per square centimeter.

[0037] Figure 4 This is a graph showing the current density versus voltage (JV) curves of the semi-transparent perovskite solar cell provided in Embodiment 3 of the present invention under illumination with an intensity of 100 milliwatts per square centimeter.

[0038] Figure 5 This is a graph showing the current density versus voltage (JV) curves of the semi-transparent perovskite solar cell provided in Embodiment 4 of the present invention under illumination with an intensity of 100 milliwatts per square centimeter.

[0039] Figure 6 This is a graph showing the current density versus voltage (JV) curves of the semi-transparent perovskite solar cell provided in Embodiment 5 of the present invention under illumination with an intensity of 100 milliwatts per square centimeter.

[0040] Figure 7 This is a graph showing the current density versus voltage (JV) curves of the semi-transparent perovskite solar cell provided in Embodiment 6 of the present invention under illumination with an intensity of 100 milliwatts per square centimeter.

[0041] Figure 8 This is a graph showing the current density versus voltage (JV) curves of the semi-transparent perovskite solar cell provided in Embodiment 7 of the present invention under illumination with an intensity of 100 milliwatts per square centimeter.

[0042] Figure 9 This is a graph showing the current density versus voltage (JV) curves of the semi-transparent perovskite solar cell provided in Comparative Example 1 of the present invention under illumination with an intensity of 100 milliwatts per square centimeter.

[0043] Figure 10 This is a graph showing the current density versus voltage (JV) curves of the semi-transparent perovskite solar cell provided in Comparative Example 2 of the present invention under illumination with an intensity of 100 milliwatts per square centimeter.

[0044] Figure label:

[0045] 1. Substrate; 2. Transparent anode layer; 3. Anode transport layer; 4. Perovskite layer; 5. Cathode transport layer; 6. Polyethyleneimine protective layer; 7. ITO electrode. Detailed Implementation

[0046] The following embodiments are provided to better understand the present invention and are not limited to the preferred embodiments described. They do not constitute a limitation on the content and scope of protection of the present invention. Any product that is the same as or similar to the present invention, derived by any person under the guidance of the present invention or by combining the features of the present invention with other prior art, falls within the protection scope of the present invention.

[0047] For experiments not specifically described in the examples, the procedures or conditions should be followed according to the conventional experimental procedures described in the literature in this field. Reagents or instruments whose manufacturers are not specified are all commercially available conventional reagent products.

[0048] Example 1

[0049] This embodiment provides a semi-transparent perovskite solar cell, such as Figure 1 As shown, from bottom to top, it includes a substrate (1), a transparent conductive glass anode (2), an anode transport layer (3), a perovskite layer (5), a cathode transport layer (5), a polyethyleneimine protective layer (6), and an ITO electrode (7). Its specific composition and preparation method are as follows:

[0050] 1. Cleaning of the ITO glass substrate (the thickness of the transparent conductive glass anode is 150 nm, and the thickness of the glass substrate is 1.1 mm, the same below). The ITO glass substrate is ultrasonically cleaned sequentially in detergent, water, deionized water, acetone, and isopropanol solvents for 15 minutes each. The cleaned ITO substrate is then dried in a 150°C oven for 5 minutes, followed by UVO treatment for 15 minutes.

[0051] 2. Preparation of an anode transport layer on an ITO transparent glass substrate. A 2 mg / ml solution of PTAA (poly[bis(4-phenyl)(2,4,6-trimethylphenyl)amine], manufactured by Xi'an Baolai Optoelectronics Technology Co., Ltd., average molecular weight 25000) dissolved in toluene was spin-coated onto the ITO substrate at a speed of 4000 rpm. The substrate was then annealed at 150°C for 10 minutes on a heating stage to prepare an anode transport layer with a thickness of 15 nm.

[0052] 3. A perovskite layer was deposited on the substrate from the previous step using a one-step deposition method. First, 50 μL of a perovskite precursor solution (77.62 mg CsI, 162.15 mg FAI, 112.13 mg PbBr2, 2.83 mg MACl, 11.68 mg PbCl2, and 425.15 mg PbI2 dissolved in a DMSO:DMF mixture (volume ratio 1:3)) was coated onto the substrate at 5000 rpm. Next, 300 μL of the anti-solvent chlorobenzene was dropped onto the perovskite film at the 25th second of the spin-coating process. Then, the film was annealed at 100 °C for 30 minutes to obtain a perovskite layer with a thickness of 450 nm.

[0053] 4. A cathode transport layer is deposited on the perovskite layer using vacuum evaporation. A 30 nm thick C layer is vacuum-deposited onto the prepared perovskite film. 60 (Manufacturer: Xi'an Baolai Optoelectronic Technology Co., Ltd.) Specific parameters are as follows: the evaporation current starts at 6A and gradually increases, reaching approximately 25A within 10 minutes. The substrate baffle is then opened to begin evaporation. Once 30nm has been deposited, the substrate baffle is turned off, and the evaporation current is reduced to 0A. Then, at C... 60 A protective layer of polyethyleneimine (PEI) is spin-coated onto the top layer. The specific procedure is as follows: Weigh a certain amount of PEI (manufacturer: Beijing Innocare Technology Co., Ltd., average molecular weight 1800). After dissolving it in isopropanol solution to prepare a solution with a concentration of 0.5 mg / ml, stir it on a stirring table at room temperature for about 30 minutes. During spin coating, adjust the speed of the spin coater to 5000 rpm for 30 seconds. After spin coating, immediately anneal it on a hot plate at 100°C for 5 minutes to prepare a polyethyleneimine protective layer with a thickness of about 1 nm.

[0054] 5. Finally, a 100 nm ITO electrode was deposited using vacuum sputtering to obtain a perovskite solar cell. The ITO sputtering conditions were: sputtering power 100 W, sputtering time 50 min, argon flow rate 60 sccm, and working pressure 2 Pa.

[0055] Example 2

[0056] This embodiment provides a semi-transparent perovskite solar cell, such as Figure 1 As shown, from bottom to top, it includes a substrate (1), a transparent conductive glass anode (2), an anode transport layer (3), a perovskite layer (5), a cathode transport layer (5), a polyethyleneimine protective layer (6), and an ITO electrode (7). Its specific composition and preparation method are as follows:

[0057] 1. Cleaning of ITO glass substrate. The ITO glass substrate was ultrasonically cleaned sequentially in detergent, water, deionized water, acetone, and isopropanol solvents for 15 minutes each. The cleaned ITO substrate was then dried in a 150°C oven for 5 minutes, followed by UVO treatment for 15 minutes.

[0058] 2. Preparation of an anode transport layer on an ITO transparent glass substrate. A 2 mg / ml solution of PTAA (poly[bis(4-phenyl)(2,4,6-trimethylphenyl)amine], manufactured by Xi'an Baolai Optoelectronics Technology Co., Ltd., molecular weight 25000) dissolved in toluene was spin-coated onto the ITO substrate at a speed of 4000 rpm. The substrate was then annealed at 150°C for 10 minutes on a heating stage to prepare an anode transport layer with a thickness of 15 nm.

[0059] 3. A perovskite layer was deposited on the substrate from the previous step using a one-step deposition method. First, 50 μL of a perovskite precursor solution (77.62 mg CsI, 162.15 mg FAI, 112.13 mg PbBr2, 2.83 mg MACl, 11.68 mg PbCl2, and 425.15 mg PbI2 dissolved in a DMSO:DMF (1:3) mixture) was coated onto the substrate at 5000 rpm. Next, 300 μL of the anti-solvent chlorobenzene was dropped onto the perovskite film at the 25th second of the spin-coating process. Then, the film was annealed at 100 °C for 30 minutes to obtain a perovskite layer with a thickness of 450 nm.

[0060] 4. A cathode transport layer is deposited on the perovskite layer using vacuum evaporation. A 30 nm thick C layer is vacuum-deposited onto the prepared perovskite film. 60(Manufacturer: Xi'an Baolai Optoelectronic Technology Co., Ltd.) Specific parameters are as follows: the evaporation current starts at 6A and gradually increases, reaching approximately 25A within 10 minutes. The substrate baffle is then opened to begin evaporation. Once 30nm has been deposited, the substrate baffle is turned off, and the evaporation current is reduced to 0A. Then, at C... 60 A polyethyleneimine (PEI) protective layer is spin-coated onto the top layer. The specific procedure is as follows: a certain amount of PEI (manufacturer: Beijing Innocare Technology Co., Ltd., average molecular weight 1800) is weighed and dissolved in isopropanol solution to prepare a solution with a concentration of 1 mg / ml. The solution is then stirred at room temperature for approximately 30 minutes. During spin-coating, the spin coater speed is adjusted to 5000 rpm for 30 seconds. Immediately after spin-coating, the layer is annealed on a hot plate at 100°C for 5 minutes to obtain a polyethyleneimine protective layer with a thickness of approximately 2 nm.

[0061] 5. Finally, a 100 nm ITO electrode was deposited using vacuum sputtering to obtain a perovskite solar cell. The ITO sputtering conditions were: sputtering power 100 W, sputtering time 50 min, argon flow rate 60 sccm, and working pressure 2 Pa.

[0062] Example 3

[0063] This embodiment provides a semi-transparent perovskite solar cell, such as Figure 1 As shown, from bottom to top, it includes a substrate (1), a transparent conductive glass anode (2), an anode transport layer (3), a perovskite layer (5), a cathode transport layer (5), a polyethyleneimine protective layer (6), and an ITO electrode (7). Its specific composition and preparation method are as follows:

[0064] 1. Cleaning of ITO glass substrate. The ITO glass substrate was ultrasonically cleaned sequentially in detergent, water, deionized water, acetone, and isopropanol solvents for 15 minutes each. The cleaned ITO substrate was then dried in a 150°C oven for 5 minutes, followed by UVO treatment for 15 minutes.

[0065] 2. Preparation of an anode transport layer on an ITO transparent glass substrate. A 2 mg / ml solution of PTAA (poly[bis(4-phenyl)(2,4,6-trimethylphenyl)amine], manufactured by Xi'an Baolai Optoelectronics Technology Co., Ltd., molecular weight 25000) dissolved in toluene was spin-coated onto the ITO substrate at a speed of 4000 rpm. The substrate was then annealed at 150°C for 10 minutes on a heating stage to prepare an anode transport layer with a thickness of 15 nm.

[0066] 3. A perovskite layer was deposited on the substrate from the previous step using a one-step deposition method. First, 50 μL of a perovskite precursor solution (77.62 mg CsI, 162.15 mg FAI, 112.13 mg PbBr2, 2.83 mg MACl, 11.68 mg PbCl2, and 425.15 mg PbI2 dissolved in a DMSO:DMF (1:3) mixture) was coated onto the substrate at 5000 rpm. Next, 300 μL of the anti-solvent chlorobenzene was dropped onto the perovskite film at the 25th second of the spin-coating process. Then, the film was annealed at 100 °C for 30 minutes to obtain a perovskite layer with a thickness of 450 nm.

[0067] 4. A cathode transport layer is deposited on the perovskite layer using vacuum evaporation. A 30 nm thick C layer is vacuum-deposited onto the prepared perovskite film. 60 (Manufacturer: Xi'an Baolai Optoelectronic Technology Co., Ltd.) Specific parameters are as follows: the evaporation current starts at 6A and gradually increases, reaching approximately 25A within 10 minutes. The substrate baffle is then opened to begin evaporation. Once 30nm has been deposited, the substrate baffle is turned off, and the evaporation current is reduced to 0A. Then, at C... 60 A polyethyleneimine (PEI) protective layer is spin-coated onto the top layer. The specific procedure is as follows: a certain amount of PEI (manufacturer: Beijing Innocare Technology Co., Ltd., average molecular weight 1800) is weighed and dissolved in isopropanol solution to prepare a solution with a concentration of 2 mg / ml. The solution is then stirred at room temperature for approximately 30 minutes. During spin-coating, the spin coater speed is adjusted to 5000 rpm for 30 seconds. Immediately after spin-coating, the layer is annealed on a hot plate at 100°C for 5 minutes to obtain a polyethyleneimine protective layer with a thickness of approximately 4 nm.

[0068] 5. Finally, a 100 nm ITO electrode was deposited using vacuum sputtering to obtain a perovskite solar cell. The ITO sputtering conditions were: sputtering power 100 W, sputtering time 50 min, argon flow rate 60 sccm, and working pressure 2 Pa.

[0069] Example 4

[0070] This embodiment provides a semi-transparent perovskite solar cell. Compared with Embodiment 2, the difference lies in the preparation method of the perovskite layer. The specific preparation method is as follows:

[0071] A perovskite layer was deposited on the substrate from the previous step using a one-step deposition method. First, 50 μL of a perovskite precursor solution (19.5 mg CsI, 219.5 mg FAI, 15.9 mg RbI, 8.4 mg MABr, 27.5 mg PbBr2, 656.9 mg PbI2) was coated onto the substrate at 5000 rpm. Next, 300 μL of the anti-solvent chlorobenzene was dropped onto the perovskite film at the 25th second of the spin coating process. The film was then annealed at 100 °C for 20 minutes to obtain a perovskite layer with a thickness of 700 nm.

[0072] Example 5

[0073] This embodiment provides a semi-transparent perovskite solar cell. Compared with Embodiment 2, the difference lies in the preparation method of the anode transport layer. The specific preparation method is as follows:

[0074] An anode transport layer was prepared on an ITO transparent glass substrate. A 0.5 mg / ml solution of 2PACz (Chinese name: [2-(9H-carbazole-9-yl)ethyl]phosphoric acid, manufactured by Xi'an Baolai Optoelectronic Technology Co., Ltd.) dissolved in ethanol was spin-coated onto the ITO substrate at 3000 rpm for 30 s. The substrate was then annealed at 100 °C for 10 minutes to obtain an anode transport layer with a thickness of 0.8 nm.

[0075] Example 6

[0076] This embodiment provides a semi-transparent perovskite solar cell. The difference from Embodiment 2 lies in the preparation method of the cathode transport layer. Specifically, the preparation is as follows:

[0077] A cathode transport layer was prepared on the perovskite layer using a spin-coating method. PC was then spin-coated onto the prepared perovskite film. 61 BM (manufacturer: Xi'an Baolai Optoelectronic Technology Co., Ltd., purity: 99%), spin coating parameters are 4000 rpm, 30 s.

[0078] Example 7

[0079] This embodiment provides a semi-transparent perovskite solar cell. Compared with Embodiment 2, the difference lies in the sputtering conditions in step 5: the sputtering conditions for ITO are: sputtering power of 80W, sputtering time of 50min, argon flow rate of 60sccm, and working pressure of 2Pa.

[0080] Comparative Example 1

[0081] This comparative example provides a semi-transparent perovskite solar cell, the specific composition and preparation method of which are as follows:

[0082] 1. Cleaning of ITO glass substrate. The ITO glass substrate was ultrasonically cleaned sequentially in detergent, water, deionized water, acetone, and isopropanol solvents for 15 minutes each. The cleaned ITO substrate was then dried in a 150°C oven for 5 minutes, followed by UVO treatment for 15 minutes.

[0083] 2. An anode transport layer was prepared on an ITO transparent glass substrate. A PTAA solution of 2 mg / ml in toluene was spin-coated onto the ITO substrate at 4000 rpm, and then annealed at 150°C for 10 minutes on a heating stage to obtain an anode transport layer with a thickness of 15 nm.

[0084] 3. A perovskite layer was deposited on the substrate from the previous step using a one-step deposition method. First, 50 μL of a perovskite precursor solution (77.62 mg CsI, 162.15 mg FAI, 112.13 mg PbBr2, 2.83 mg MACl, 11.68 mg PbCl2, and 425.15 mg PbI2 dissolved in a DMSO:DMF (1:3) mixture) was coated onto the substrate at 5000 rpm. Next, 300 μL of the anti-solvent chlorobenzene was dropped onto the perovskite film at the 25th second of the spin-coating process. Then, the film was annealed at 100 °C for 30 minutes to obtain a perovskite layer with a thickness of 450 nm.

[0085] 4. A cathode transport layer is deposited on the perovskite layer using vacuum evaporation. A 30 nm thick C layer is vacuum-deposited onto the prepared perovskite film. 60 (Manufacturer: Xi'an Baolai Optoelectronic Technology Co., Ltd.) Specific parameters are as follows: The evaporation current starts at 6A and gradually increases to approximately 25A within 10 minutes. The substrate baffle is then opened to begin evaporation. Once 30nm of material has been deposited, the substrate baffle is turned off, and the evaporation current is reduced to 0A. Then, 8nm of BCP (Chinese name: 2,9-dimethyl-4,7-biphenyl-1,10-phenanthroline, manufacturer: Xi'an Baolai Optoelectronic Technology Co., Ltd.) is deposited. The evaporation current is gradually increased from 0A to 3A, and the baffle is opened for further evaporation. Evaporation is stopped once the BCP thickness reaches 8nm.

[0086] 5. Finally, a 100 nm ITO electrode was deposited using vacuum sputtering to obtain a perovskite solar cell. The ITO sputtering conditions were: sputtering power 100 W, sputtering time 50 min, argon flow rate 60 sccm, and working pressure 2 Pa.

[0087] Comparative Example 2

[0088] This comparative example provides a semi-transparent perovskite solar cell, which differs from Example 2 only in the composition of the polyethyleneimine protective layer, as shown below. The polyethyleneimine (manufactured by Beijing Innocare Technology Co., Ltd., with an average molecular weight of 4000) does not have a branched structure.

[0089]

[0090] Test case

[0091] The semi-transparent perovskite solar cells obtained in the embodiments and comparative examples of this invention were subjected to performance tests. The current density versus voltage (JV) curves measured under illumination of 100 milliwatts per square centimeter are shown below. Figure 2-10 As shown in the table below. Specific test results are also available.

[0092] Table 1

[0093]

[0094]

[0095] The data in the table above shows that the protective PEI layer plays a crucial role in the fabrication of semi-transparent perovskite solar cells with ITO as the top electrode. Comparative Example 1 shows that in the electron transport layer C... 60With BCP as the protective layer, the device's photoelectric conversion efficiency is extremely low, at only 9.81%, indicating that BCP does not play a protective role for the underlying layer at all. Branched polyethyleneimine, as a polymer, has good impact resistance. At the same time, this polymer is rich in nitrogen, which can form complexes with particles sputtered during ITO. Furthermore, the numerous amino groups on the branches can form interfacial dipoles with the ITO layer, which helps to reduce the work function of ITO and thus contributes to the improvement of the device's open-circuit voltage. Example 1 used a branched polyethyleneimine layer approximately 1 nm thick as a protective layer, which significantly improved the device parameters, ultimately achieving a photoelectric conversion efficiency of 17.09%. Example 2 used a branched polyethyleneimine layer approximately 2 nm thick as a protective layer, achieving optimal device performance with a photoelectric conversion efficiency of 18.72%. As the thickness of the branched polyethyleneimine continues to increase, the polymer's insulation properties become dominant, reducing device performance. As shown in Example 3, although the device voltage is the highest, the short-circuit current and fill factor are significantly reduced, ultimately leading to a device efficiency decrease to 14.91%. Compared to branched polyethyleneimine, linear polyethyleneimine also provides some protection, but due to the reduction in amino groups, it has a lower protective effect on the device's electrical properties. The increase in voltage did not have a significant effect. As shown in Comparative Example 2, the battery device based on linear polyethyleneimine ultimately achieved an efficiency of 16.86%, lower than that of Example 2. In the following examples, we made changes to Example 2. For instance, in Example 4, we selected perovskite with different formulations as the light absorption layer. Under the protection of branched polyethyleneimine, we still achieved relatively good device performance, with a photoelectric conversion efficiency of 18.51%. In Example 5, we replaced the anode transport layer with PACz instead of PTAA, while keeping other conditions the same as in Example 2. The final device achieved an efficiency of 18.27%, indicating that in this battery structure, PACz as the anode transport layer is slightly inferior to PTAA. In Example 6, we changed the cathode transport layer to PC... 61 BM replaces C 60 Similar device performance was achieved. This indicates that PC... 61 BM can also be used as a cathode transport layer in this semi-transparent solar cell. When sputtering ITO, we changed the sputtering power to 80W. With other conditions unchanged, the low power condition will cause the ITO conductivity to decrease, as shown in Example 7. At this time, the corresponding device also has a reduced photoelectric conversion efficiency.

[0096] Obviously, the above embodiments are merely illustrative examples for clear explanation and are not intended to limit the implementation. Those skilled in the art will recognize that other variations or modifications can be made based on the above description. It is neither necessary nor possible to exhaustively list all possible implementations here. However, obvious variations or modifications derived therefrom are still within the scope of protection of this invention.

Claims

1. A method of making a semi-transparent perovskite cell, characterized in that, Includes the following steps: S1, Obtain a substrate containing a transparent conductive glass anode, pre-treat it, and sequentially prepare an anode transport layer, a perovskite layer and a cathode transport layer; S2, a polyethyleneimine protective layer is prepared on the cathode transport layer by spin coating; The thickness of the polyethyleneimine protective layer is 1-5 nm; The polyethyleneimine has an average molecular weight of 1200-20000 and has the following structure: ； S3 uses vacuum sputtering to deposit ITO electrodes.

2. The method of claim 1, wherein the method is characterized by: In step S3, the vacuum sputtering conditions are: sputtering power 70-100W, sputtering time 30-60min, argon flow rate 40-70sccm, and working pressure 0.5-5Pa.

3. The method for preparing a semi-transparent perovskite solar cell according to claim 1, characterized in that, In step S2, the method for preparing the polyethyleneimine protective layer includes: Polyethyleneimine was dissolved in an organic solvent, spin-coated, and annealed to obtain the polyethyleneimine protective layer.

4. The semi-transparent perovskite cell according to any one of claims 1 to 3, characterized in that, From bottom to top, it includes a substrate, a transparent conductive glass anode, an anode transport layer, a perovskite layer, a cathode transport layer, a polyethyleneimine protective layer, and an ITO electrode.

5. The semi-transparent perovskite cell according to claim 4, characterized in that, The transparent conductive glass anode is at least one of FTO and ITO; And / or, the thickness of the transparent conductive glass anode is 100-200 nm.

6. The semi-transparent perovskite cell according to claim 4, wherein, The anode transport layer is at least one of PEDOT:PSS (poly(3,4-ethylenedioxythiophene / polystyrene sulfonate), PTAA (poly[bis(4-phenyl)(2,4,6-trimethylphenyl)amine]), and 2PACz ([2-(9H-carbazole-9-yl)ethyl]phosphonic acid); And / or, the thickness of the anode transport layer is 0.8-30 nm.

7. The semi-transparent perovskite solar cell according to claim 4, characterized in that, The perovskite layer has a composition of ABX3; Where A is CH3NH3 + HC(NH2)2 + Cs + One or more of them, where B is Pb 2+ Sn 2+ Cu 2+ One or more of them, where X is I - ,Br - Cl - One or more of the following; And / or, the thickness of the perovskite layer is 300-450 nm.

8. The semi-transparent perovskite cell according to claim 4, wherein, The cathode transport layer is C. 60 (C60), PC 61 At least one of BM ([6,6]-phenyl C61 butyrate), ZnO (zinc oxide), and TIPD (titanium acetylacetonate); And / or, the thickness of the cathode transport layer is 5-20 nm.

9. The semi-transparent perovskite cell according to any one of claim 4, characterized in that, The thickness of the ITO electrode is 100-300 nm.

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