Perovskite solar cell based on hydroxylation-rich hole transport layer and preparation method thereof

Abstract

The invention belongs to the technical field of new materials and new energy, and particularly relates to a perovskite solar cell based on a hydroxylation-enriched hole transport layer and a preparation method of the perovskite solar cell. The preparation method sequentially comprises the following steps: cleaning a conductive glass substrate and performing surface plasma treatment; preparing an SAM molecular'landing layer ', an SAM hole transport layer and a perovskite thin film on the substrate, and preparing an electron transport layer; and constructing an electrode on the electron transport layer to prepare the perovskite solar cell. The'landing layer 'molecules firstly react with hydroxyl groups on the substrate and are firmly combined on the substrate, so that a foundation is laid for subsequent preparation of anchoring SAM molecules. Through the quantum tunneling effect, on the premise that the charge transmission performance is not affected, the self-aggregation trend of SAM molecules is hindered, uniform distribution of the SAM molecules is promoted, an effective technical scheme is provided for preparing a uniform and compact hole transmission layer, and carrier transmission is promoted. The method is low in cost and has important practical value and economic value.

Description

Technical Field

[0001] This invention belongs to the field of new materials and new energy technology, specifically relating to a perovskite solar cell based on a hydroxylated hole transport layer and its preparation method. Background Technology

[0002] In the field of photovoltaic technology, perovskite solar cells are sparking a new technological revolution due to their advantages such as high energy conversion efficiency, low cost, and ease of fabrication. The hole transport layer plays a crucial role in perovskite solar cells, extracting and transporting photogenerated holes generated in the perovskite layer and suppressing electron backflow. Classic hole transport materials such as Spiro and PTAA, however, have limited their large-scale application due to drawbacks such as low hole mobility and high cost.

[0003] In recent years, self-assembled monolayers (SAMs) have been widely used as hole transport layers in inverted perovskite solar cells. The anchoring functional groups of SAM molecules can form monomolecular thin films on substrates. This method offers advantages such as low material consumption, no need for additives, low parasitic absorption, compatibility with tandem devices, and suitability for large-area manufacturing. It significantly improves efficiency and stability and is considered a milestone in the development of inverted perovskite solar cells.

[0004] Patent CN3118555884 A discloses a method for optimizing the NiOx / SAM hole transport layer in perovskite solar cells. This method achieves robust anchoring of SAM molecules by treating the NiOx thin film surface with O2-plasma (oxygen plasma). However, this patent only improves the interfacial properties of the NiOx / SAM bilayer hole transport layer and does not solve the problems of SAM molecule aggregation and better uniform anchoring.

[0005] SAM molecules are uniformly anchored to the substrate surface through the interaction of their anchoring functional groups with hydroxyl groups on the substrate. However, the state and quantity of hydroxyl groups on the substrate are uncertain and unreliable, preventing SAM molecules from being fully anchored to the substrate surface. This uneven deposition of SAM molecules on the substrate poses a significant challenge to the large-scale fabrication of perovskite solar cells. Therefore, there is an urgent need to provide a method for fabricating perovskite solar cells using hydroxyl-rich molecules as the "landing layer" for SAM molecules, achieving uniform deposition of SAM molecules on the substrate. Summary of the Invention

[0006] The technical problem to be solved by this invention is to provide a perovskite solar cell based on a hydroxylated hole transport layer and its preparation method. This method anchors SAM molecules by increasing the number of anchoring points, inhibiting SAM molecule aggregation, improving the uniformity of the SAM layer, and effectively solving the aggregation problem caused by insufficient SAM molecule anchoring. This provides favorable conditions for subsequent perovskite growth, improves the defects at the buried interface of the perovskite layer, and the perovskite solar cell prepared by this invention has the advantages of good stability, high performance, low cost, and wide applicability. It has significant theoretical and practical value and is conducive to accelerating the industrialization process of perovskite solar cells.

[0007] The technical solution adopted is as follows: A method for fabricating a perovskite solar cell based on a hydroxylated hole transport layer includes the following steps: (1) Cleaning and surface plasma treatment of commercially etched transparent conductive glass substrates; And / or, NiO is prepared on conductive glass that has undergone cleaning and surface plasma treatment. x layer; (2) After coating the substrate with a hydroxyl-rich solution, annealing forms the “landing layer” of SAM molecules; (3) Prepare a SAM hole transport layer on the “landing layer” of SAM molecules; (4) Coating a perovskite thin film on the hole transport layer to form a perovskite structure light-absorbing layer, and then preparing an electron transport layer on the perovskite structure light-absorbing layer. (5) Construct electrodes on the electron transport layer to prepare perovskite solar cells. The electrodes used are metal electrodes.

[0008] Preferably, in step (1), the conductive glass is FTO (fluorine-doped tin dioxide transparent conductive glass) or ITO (indium tin oxide transparent conductive glass); the substrate can be selected as FTO or ITO, or step (2) can be performed after preparing a NiOx layer on ITO or FTO.

[0009] The cleaning process involves cleaning the glass substrate in the following order: cleaning agent, deionized water, and ethanol. Then, the glass substrate is placed in a plasma cleaner and treated at 40 W for 1–2 minutes.

[0010] Preferably, the solvent for the hydroxyl-rich solution is deionized water, and the hydroxyl-rich molecules include, but are not limited to, 1,2-bis(trimethylsiloxy)ethane or polyvinyl phosphate ammonium; the hydroxyl-rich solution is prepared using deionized water and shaken for 5 to 20 minutes; wherein the concentration of the polyvinyl phosphate ammonium solution is 0.01 to 0.05 mg / mL, and the concentration of the 1,2-bis(trimethylsiloxy)ethane solution is 0.5 to 1.5 mg / mL.

[0011] 1,2-bis(trimethylsiloxy)ethane can generate hydroxyl groups through hydrolysis, and polyvinyl alcohol ammonium phosphate can generate hydroxyl groups during thermal annealing.

[0012] Preferably, the hydroxyl-rich solution is spin-coated at a speed of 3000 rpm for 20–50 s, wherein the heat annealing temperature of the polyvinyl ammonium phosphate wet film is 80–150°C for 1–5 min, and the heat annealing temperature of the 1,2-bis(trimethylsiloxy)ethane wet film is 100–150°C for 5–10 min.

[0013] Preferably, in step (3), the SAM molecule used is [2-(3,6-dimethoxy-9H-carbazole-9-yl)ethyl]phosphonic acid (MeO-2PACz); MeO-2PACz is dissolved in ethanol, shaken evenly, and a SAM solution is prepared, with a concentration of 0.5-2.0 mg / mL.

[0014] Preferably, in step (4), the perovskite film used is a Cs film prepared by a two-step spin-coating method. 0.03 FA 0.97 PbI3 or Cs prepared by one-step spin coating method 0.05 MA 0.05 FA 0.9 )Pb(I 0.93 Br 0.07 3.

[0015] Preferred, Cs 0.03 FA 0.97 The PbI3 precursor solution was prepared as follows: PbI2 and CsI were dissolved in DMF (N,N-dimethylformamide) and DMSO (dimethyl sulfoxide), and stirred evenly at 60–70°C to obtain the PbI2 precursor solution; FAI (formamidinium hydroiodate) and MACl (methylammonium chloride) were dissolved in isopropanol, stirred at room temperature for 20–30 min, cooled, and filtered through a 0.22 μm filter to obtain the CsI precursor solution. 0.03 FA 0.97 PbI3 precursor solution; Or, (Cs) 0.05 MA 0.05 FA 0.9 )Pb(I 0.93 Br 0.07 The preparation method of the precursor solution is as follows: PbI2, CsI, PbBr2, MACl, MABr (methylammonium bromide), and FAI are added to a mixed solvent of DMF and DMSO, stirred at 40-50°C for 1 h, cooled, and filtered through a 0.22 μm filter to prepare (CsI) 0.05 MA 0.05 FA0.9 )Pb(I 0.93 Br 0.07 )3. Precursor solution.

[0016] Preferably, in step (4), the electron transport layer is methyl [6,6]-phenyl-C61-butyrate (PC). 61 BM) and 2,9-dimethyl-4,7-biphenyl-1,10-o-phenanthroline (BCP); PC 61 BM is dissolved in chlorobenzene and stirred at room temperature for more than 12 hours to obtain PC. 61 BM solution: Dissolve BCP in isopropanol and heat and stir at 55°C for 0.5–1.5 h to prepare BCP solution; The electron transport layer was fabricated in two steps: first, PC was spin-coated at 1500 rpm. 61 Spin-coat BM solution for 30 s, then heat-anneal at 90–120°C for 10 min; then spin-coat BCP solution at 3000 rpm for 30 s, and heat-anneal at 90–120°C for 3 min.

[0017] Preferably, in step (5), a high-vacuum metal electrode coating machine is used to prepare a metal electrode to construct a perovskite solar cell; wherein, the annealing in step (2) is performed in an air atmosphere, and steps (3), (4) and (5) are all performed in a glove box under a nitrogen atmosphere.

[0018] The present invention also provides a perovskite solar cell based on a hydroxylated hole transport layer, which is prepared by the method described in the present invention.

[0019] Compared with the prior art, the beneficial effects of the present invention are as follows: (1) This invention comprehensively considers the specific polarity, volatility, cost, and photoelectric performance requirements of the hydroxyl-rich molecules in the "landing layer" as well as the needs for fabricating complete devices. Through extensive experiments, hydroxyl-rich molecules, including but not limited to 1,2-bis(trimethylsiloxy)ethane and polyvinyl ammonium phosphate, were finally selected. The "landing layer" molecules first interact with the hydroxyl groups on the substrate, firmly binding to the substrate and laying the foundation for the subsequent preparation of anchored SAM molecules. Through the quantum tunneling effect, the self-aggregation tendency of SAM molecules is hindered without affecting the charge transport performance, promoting the uniform distribution of SAM molecules and providing an effective technical solution for preparing a uniform and dense hole transport layer, thus promoting carrier transport. This method has advantages such as low cost, simple operation, and good film formation.

[0020] (2) By introducing hydroxyl-rich molecules as the “landing layer” of SAM molecules, this invention effectively improves the quality of perovskite thin films, increases grain size, improves crystallinity, and enhances the performance of perovskite solar cells.

[0021] (3) Battery open-circuit voltage in this invention V OC Short-circuit current density J SC The fill factor (FF) and photoelectric conversion efficiency (PCE) were both improved compared to the blank sample. This resulted in a perovskite solar cell with good stability and high performance, thus accelerating the industrialization process of perovskite solar cells and possessing significant practical and economic value. Attached Figure Description

[0022] Figure 1 This is a schematic diagram of the perovskite solar cell device structure.

[0023] Figure 2 The JV curves are shown for the inverse organic-inorganic hybrid perovskite solar cells prepared according to Comparative Example 1 and Example 1.

[0024] Figure 3 The JV curves are shown for the inverse organic-inorganic hybrid perovskite solar cells prepared according to Comparative Example 2 and Example 2.

[0025] Figure 4 SEM images of the trans-structured organic-inorganic hybrid perovskite films prepared according to Comparative Example 1 and Example 1.

[0026] Figure 5 SEM images of the trans-structured organic-inorganic hybrid perovskite films prepared according to Comparative Example 2 and Example 2. Detailed Implementation

[0027] The accompanying drawings are for illustrative purposes only; to make the objectives and technical solutions of the present invention clearer, the present invention will be further described in detail below with reference to embodiments. The present invention is not limited to the specific examples and embodiments described herein. Any further improvements and modifications can be easily made by those skilled in the art without departing from the spirit and scope of the present invention, and all such improvements and modifications fall within the protection scope of the present invention. Unless otherwise specified.

[0028] Furthermore, the technical features involved in the various embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other. The reagents used in the present invention are available through conventional commercial channels, and the testing methods and equipment used are conventional methods and equipment in this technical field.

[0029] like Figure 1As shown, a perovskite solar cell based on a hydroxyl-rich hole transport layer includes a substrate, a "landing layer," a SAM layer, a perovskite light-absorbing layer, an electron transport layer, and electrodes. The electrodes are commonly used metal electrodes, such as copper electrodes or silver electrodes. The substrate is selected as ITO or ITO / NiO. x The "landing layer" molecule was chosen to be polyvinyl ammonium phosphate or 1,2-bis(trimethylsiloxy)ethane; the perovskite absorber layer structure was chosen to be prepared by a two-step Cs method. 0.03 FA 0.97 PbI3 or one-step preparation (Cs) 0.05 MA 0.05 FA 0.9 )Pb(I 0.93 Br 0.07 3.

[0030] Example 1 A method for fabricating perovskite solar cells based on hydroxylated hole transport layers, wherein the substrate is ITO and Cs is prepared in two steps. 0.03 FA 0.97 The PbI3 perovskite light-absorbing layer, with the "landing layer" molecule selected as polyvinyl ammonium phosphate, specifically includes the following steps: (1) Use commercially available ITO glass substrates with special etched patterns and clean them in the following order: cleaning agent, deionized water, and ethanol. Then place the glass substrates in a plasma cleaner and treat them at 40 W for 1 min.

[0031] (2) Prepare a 0.025 mg / mL polyvinyl alcohol ammonium phosphate solution using deionized water and shake for 10 min.

[0032] (3) Spin-coat 85 μL of solution from step (2) at 3000 rpm for 30 s, and then heat-anneal at 100°C for 1 min.

[0033] (4) Dissolve 1.0 mg MeO-2PACz in 1 mL of ethanol and shake for 10 min to prepare SAM solution.

[0034] (5) Spin-coat 85 μL of SAM solution at 3000 rpm for 30 s, and then heat-anneal at 100°C for 10 min.

[0035] (6) Preparation of perovskite precursor solution: 1037.3 mg PbI2 and 20.5 mg CsI were dissolved in 1800 μL LMF and 200 μL DMSO, and stirred at 70°C for more than 12 h to obtain the PbI2 precursor solution. Preparation of perovskite cation solution: 180 mg FAI and 20 mg MACl were dissolved in 2 mL isopropanol, and stirred at room temperature for 30 min to obtain the FAI precursor solution. Both precursor solutions were filtered through a 0.22 μm filter before use.

[0036] (7) Preparation of perovskite layer: Spin-coat 70 μL of PbI2 solution at 2300 rpm for 30 s, then heat-anneal at 70°C for 1 min. Spin-coat cation layer: Spin-coat 85 μL of FAI solution at 2900 rpm for 30 s, transfer ITO to air, and heat-anneal at 150°C for 10 min to prepare Cs. 0.03 FA 0.9 Perovskite in the 7PbI3 system.

[0037] (8) Take 21 mg of PC 61 BM was dissolved in 1 mL of chlorobenzene and stirred at room temperature for more than 12 h to prepare PC. 61 BCP solution: Dissolve 1 mg of BCP in 2 mL of isopropanol, heat and stir for 1 h to prepare the BCP solution. (9) The preparation of the electron transport layer is divided into two steps: ① spin-coating 65 μL of PC at a speed of 1500 rpm. 61 ① Spin-coat 85 μL of BCP solution at 3000 rpm for 30 s, then heat-anneal at 100°C for 10 min.

[0038] (10) Scrape off the edge film, prepare metal electrodes using a high vacuum metal electrode coating machine, and construct perovskite solar cells.

[0039] In steps (1), (2), (3) and (7), the second thermal annealing operation is carried out in an air atmosphere, while the remaining steps are carried out in a glove box in a nitrogen atmosphere.

[0040] Example 2 A method for fabricating perovskite solar cells based on hydroxylated hole transport layers, wherein the substrate is ITO / NiO. x One-step preparation of (Cs) 0.05 MA 0.05 FA 0.9 )Pb(I 0.93 Br 0.073. Perovskite light-absorbing layer, with the "landing layer" molecule selected as 1,2-bis(trimethylsiloxy)ethane, specifically including the following steps: (1) Use commercially available ITO glass substrates with special etched patterns and clean them in the following order: cleaning agent, deionized water, and ethanol. Then place the glass substrates in a plasma cleaner and treat them at 40 W for 1 min.

[0041] (2) Take 10 mg NiO x Nanoparticles were dissolved in 1 mL of deionized water and sonicated for 10 min to prepare a NiOx solution; (3) Spin-coat 70 μL of NiOx solution at 2000 rpm for 30 s, and then heat-anneal at 150°C for 20 min.

[0042] (4) Prepare a 1.2 mg / mL solution of 1,2-bis(trimethylsiloxy)ethane using deionized water and shake for 1 h.

[0043] (5) Spin-coat 85 μL of solution from step (4) at 3000 rpm for 30 s, and then heat-anneal at 100°C for 10 min.

[0044] (6) Dissolve 1.0 mg MeO-2PACz in 1 mL of ethanol and shake for 10 min to prepare SAM solution.

[0045] (7) Spin-coat 85 μL of SAM solution at 3000 rpm for 30 s, and then heat-anneal at 100°C for 10 min.

[0046] (8) 572.0 mg PbI2, 18.2 mg CsI, 220 mg PbBr2, 8.8 mg MACl, 6.7 mg MABr, and 196.1 mg FAI were added to a mixed solvent of 0.692 mL DMF and 0.173 mL DMSO. The mixture was stirred at 45°C for 1 h, cooled, and filtered through a 0.22 μm filter to prepare (CsI). 0.05 MA 0.05 FA 0.9 )Pb(I 0.93 Br 0.07 )3. Precursor solution.

[0047] (9) Take 100 μL of the perovskite precursor solution prepared in step (8) and spin-coat it onto the hole transport layer film of step (7). Spin-coating is set to a two-step operation. The parameters for the first step are adjusted to 1000 rpm and rotated for 5 s. The parameters for the second step are adjusted to 4000 rpm and rotated for 30 s. Take 100 μL of the perovskite solution and deposit it onto the SAM film. At the 15th second countdown of the second step, rinse the substrate uniformly and rapidly with the antisolvent chlorobenzene within 1 s. Heat anneal at 100°C for 30 min. Prepare (Cs 0.05 MA 0.05 FA 0.9 )Pb(I 0.93 Br 0.07 )3 system of perovskite.

[0048] (10) 21 mg of PC 61 BM is dissolved in 1 mL of chlorobenzene and stirred at room temperature for at least 12 hours to produce PC. 61 BCP solution: Dissolve 1 mg of BCP in 2 mL of isopropanol and heat and stir at 55°C for 1 h to prepare the BCP solution. (11) The preparation of the electron transport layer is divided into two steps: ① spin-coating 65 μL of PC at a speed of 1500 rpm. 61 ① Spin-coat 85 μL of BCP solution at 3000 rpm for 30 s, then heat-anneal at 100°C for 10 min.

[0049] (12) Scrape off the edge film, prepare metal electrodes using a high vacuum metal electrode coating machine, and construct perovskite solar cells.

[0050] Steps (1), (2), (3), (4) and (5) are performed in an air atmosphere, while the remaining steps are performed in a glove box under a nitrogen atmosphere.

[0051] Comparative Example 1 A method for fabricating perovskite solar cells (ITO substrate, two-step preparation of Cs) 0.03 FA 0.97 PbI3 perovskite light-absorbing layer), including the following steps: (1) Use commercially available ITO glass substrates with special etched patterns and clean them in the following order: cleaning agent, deionized water, and ethanol. Then place the glass substrates in a plasma cleaner and treat them at 40 W for 1 min.

[0052] (2) Dissolve 1.0 mg MeO-2PACz in 1 mL of ethanol and shake for 10 min to prepare SAM solution.

[0053] (3) Spin-coat 85 μL of SAM solution at 3000 rpm for 30 s, and then heat-anneal at 100°C for 10 min.

[0054] (4) Preparation of perovskite precursor solution: 1037.3 mg of PbI2 and 20.5 mg of CsI were dissolved in 1350 μL of DMF (N,N-dimethylformamide) and 150 μL of DMSO (dimethyl sulfoxide), and stirred at 70°C for more than 12 h to obtain the PbI2 precursor solution. Preparation of perovskite cation solution: 180 mg of FAI (formamidinium hydroiodide) and 20 mg of MACl (methylammonium chloride) were dissolved in 2 mL of isopropanol, and stirred at room temperature for 30 min to obtain the FAI precursor solution. Both precursor solutions were filtered through a 0.22 μm filter.

[0055] (5) Spin-coating perovskite precursor solution layer: 70 μL of PbI2 solution was spin-coated at 2300 rpm for 30 s, followed by thermal annealing at 70°C for 1 min. Spin-coating cation layer: FAI solution was spin-coated at 2900 rpm for 30 s, ITO was transferred to air, and thermal annealing was performed at 150°C for 10 min to prepare Cs. 0.03 FA 0.97 Perovskites in the PbI3 system.

[0056] (6) Take 21 mg of PC 61 BM is dissolved in 1 mL of chlorobenzene and stirred at room temperature for at least 12 hours to produce PC. 61 BCP solution: Dissolve 1 mg of BCP in 2 mL of isopropanol, heat and stir for 1 h to prepare the BCP solution. (7) The preparation of the electron transport layer is divided into two steps: ① spin-coating 65 μL of PC at a speed of 1500 rpm. 61 ① Spin-coat 85 μL of BCP solution at 2000 rpm for 30 s, then heat-anneal at 100°C for 3 min.

[0057] (8) Scrape off the edge film, prepare metal electrodes using a high vacuum metal electrode coating machine, and construct perovskite solar cells.

[0058] Among them, the second thermal annealing operations in steps (1) and (5) are carried out in an air atmosphere, while the remaining steps are carried out in a glove box in a nitrogen atmosphere.

[0059] Comparative Example 2 A method for fabricating perovskite solar cells (substrate is ITO / NiO) xOne-step preparation of (Cs) 0.05 MA 0.05 FA 0.9 )Pb(I 0.93 Br 0.07 )3. Perovskite light-absorbing layer), including the following steps: (1) Use commercially available ITO glass substrates with special etched patterns and clean them in the following order: cleaning agent, deionized water, and ethanol. Then place the glass substrates in a plasma cleaner and treat them at 40 W for 1 min.

[0060] (2) Take 10 mg NiO x Dissolve in 1 mL of deionized water and sonicate for 10 min to prepare NiOx solution.

[0061] (3) Spin-coat 70 μL of NiOx solution at 2000 rpm for 30 s, and then heat-anneal at 150°C for 20 min.

[0062] (4) Dissolve 1.0 mg MeO-2PACz in 1 mL of ethanol and shake for 10 min to prepare SAM solution.

[0063] (5) Spin-coat 85 μL of SAM solution at 3000 rpm for 30 s, and then heat-anneal at 150°C for 10 min.

[0064] (6) 572.0 mg PbI2, 18.2 mg CsI, 220 mg PbBr2, 8.8 mg MACl, 6.7 mg MABr (methylammonium bromide), and 196.1 mg FAI were added to a mixed solvent of 0.692 mL DMF and 0.173 mL DMSO. The mixture was stirred at 45°C for 1 h, cooled to room temperature, and filtered through a 0.22 μm filter to prepare (CsI) 0.05 MA 0.05 FA 0.9 )Pb(I 0.93 Br 0.07 )3. Precursor solution.

[0065] (7) Take 100 μL of the perovskite precursor solution prepared in step (6) and spin-coat it onto the hole transport layer in step (5). The spin-coating is set to a two-step operation. The parameters for the first step are adjusted to 1000 rpm and rotated for 5 s. The parameters for the second step are adjusted to 4000 rpm and rotated for 30 s. Take 100 μL of the perovskite solution and deposit it onto the SAM film. At the 15th second countdown of the second step, rinse the substrate uniformly and rapidly with the antisolvent chlorobenzene within 1 s. Heat anneal at 100°C for 30 min. Prepare (Cs 0.05 MA 0.05FA 0.9 )Pb(I 0.93 Br 0.07 )3 system of perovskite.

[0066] (8) Take 21 mg of PC 61 BM is dissolved in 1 mL of chlorobenzene and stirred at room temperature for at least 12 hours to produce PC. 61 BCP solution: Dissolve 1 mg of BCP in 2 mL of isopropanol, heat and stir for 1 h to prepare the BCP solution. (9) The preparation of the electron transport layer is divided into two steps: ① spin-coating 65 μL of PC at a speed of 1500 rpm. 61 ① Spin-coat 85 μL of BCP solution at 3000 rpm for 30 s, then heat-anneal at 100°C for 10 min.

[0067] (10) Scrape off the edge film, prepare metal electrodes using a high vacuum metal electrode coating machine, and construct perovskite solar cells.

[0068] Steps (1), (2), and (3) are performed in an air atmosphere, while the remaining steps are performed in a glove box under a nitrogen atmosphere.

[0069] The batteries prepared in Examples 1 and 2 and Comparative Examples 1 and 2 were subjected to performance tests, and the results are shown in Table 1.

[0070] Table 1. Comparison of battery performance parameters between Comparative Examples 1-2 and Examples 1-2 like Figure 2 , Figure 3 As shown in Table 1, it can be seen that in the method of the present invention, the SAM layer is modified with polyvinyl alcohol ammonium phosphate or 1,2-bis(trimethylsiloxy)ethane as a "landing layer", which effectively improves the quality of the perovskite film and significantly enhances the battery performance of the prepared battery device.

[0071] like Figure 4 and Figure 5 As shown in the figure, it can be seen that modifying the SAM layer with polyvinyl alcohol ammonium phosphate or 1,2-bis(trimethylsiloxy)ethane as a "landing layer" promotes the uniform distribution of SAM molecules, reduces the porosity of the prepared perovskite film, increases the grain size, and makes the bulk phase growth more regular, effectively improving the quality of the perovskite film.

[0072] Example 3 A method for fabricating perovskite solar cells based on hydroxylated hole transport layers, wherein the substrate is ITO / NiO. x Two-step preparation of Cs0.03 FA 0.97 The PbI3 perovskite light-absorbing layer, with the "landing layer" molecule chosen as polyvinyl alcohol ammonium phosphate.

[0073] Other areas not mentioned are the same as in Example 1.

[0074] Example 4 A method for fabricating perovskite solar cells based on hydroxylated hole transport layers, wherein the substrate is ITO, and (Cs) is fabricated in one step. 0.05 MA 0.05 FA 0.9 )Pb(I 0.93 Br 0.07 )3 Perovskite light-absorbing layer, 1,2-bis(trimethylsiloxy)ethane.

[0075] Other areas not mentioned are the same as in Example 1.

[0076] Of course, the above description is not intended to limit the present invention, and the present invention is not limited to the examples given above. Any changes, modifications, additions or substitutions made by those skilled in the art within the scope of the present invention, as long as they conform to the purpose of the present invention and do not violate the present invention's method for preparing a perovskite solar cell using hydroxyl-rich molecules as a "buffer layer" for SAM molecules, should also fall within the protection scope of the present invention.

Claims

1. A method for fabricating a perovskite solar cell based on a hydroxylated hole transport layer, characterized in that, Includes the following steps: (1) Cleaning and surface plasma treatment of commercially etched transparent conductive glass substrates; And / or, NiO is prepared on conductive glass that has undergone cleaning and surface plasma treatment. x layer; (2) After coating the substrate with a hydroxyl-rich solution, annealing forms the "landing layer" of SAM molecules; (3) Prepare a SAM hole transport layer on the "landing layer" of SAM molecules; (4) Coating a perovskite thin film on the hole transport layer to form a perovskite structure light-absorbing layer, and then preparing an electron transport layer on the perovskite structure light-absorbing layer. (5) Construct electrodes on the electron transport layer to prepare perovskite solar cells. The electrodes used are metal electrodes.

2. The method for fabricating a perovskite solar cell based on a hydroxylated hole transport layer according to claim 1, characterized in that, In step (1), the conductive glass is FTO or ITO; The cleaning process involves cleaning the glass substrate in the following order: cleaning agent, deionized water, and ethanol. Then, the glass substrate is placed in a plasma cleaner and treated at 40 W for 1–2 minutes.

3. The method for fabricating a perovskite solar cell based on a hydroxylated hole transport layer according to claim 1, characterized in that, The solvent for the hydroxyl-rich solution is deionized water, and the hydroxyl-rich molecules are 1,2-bis(trimethylsiloxy)ethane or polyvinyl alcohol ammonium phosphate. The hydroxyl-rich solution is prepared using deionized water and shaken for 5–20 min. The concentration of the polyvinyl alcohol ammonium phosphate solution is 0.01–0.05 mg / mL, and the concentration of the 1,2-bis(trimethylsiloxy)ethane solution is 0.5–1.5 mg / mL.

4. The method for fabricating a perovskite solar cell based on a hydroxylated hole transport layer according to claim 2, characterized in that, The hydroxyl-rich solution was spin-coated at 3000 rpm for 20–50 s. The heat annealing temperature of the polyvinyl ammonium phosphate wet film was 80–150°C for 1–5 min, and the heat annealing temperature of the 1,2-bis(trimethylsiloxy)ethane wet film was 100–150°C for 5–10 min.

5. The method for fabricating a perovskite solar cell based on a hydroxylated hole transport layer according to claim 1, characterized in that, In step (3), the SAM molecule used is [2-(3,6-dimethoxy-9H-carbazole-9-yl)ethyl]phosphonic acid; [2-(3,6-dimethoxy-9H-carbazole-9-yl)ethyl]phosphonic acid is dissolved in ethanol, shaken evenly, and a SAM solution is prepared with a concentration of 0.5-2.0 mg / mL.

6. The method for fabricating a perovskite solar cell based on a hydroxylated hole transport layer according to claim 1, characterized in that, In step (4), the perovskite film used is a Cs film prepared by a two-step spin-coating method. 0.03 FA 0.97 PbI3 or Cs prepared by one-step spin coating method 0.05 MA 0.05 FA 0.9 )Pb(I 0.93 Br 0.07 3.

7. The method for fabricating a perovskite solar cell based on a hydroxylated hole transport layer according to claim 6, characterized in that, Cs 0.03 FA 0.97 The preparation method of PbI2 precursor solution is as follows: PbI2 and CsI are dissolved in DMF and DMSO, and stirred evenly at 60-70°C to obtain PbI2 precursor solution; FAI and MACl are dissolved in isopropanol, stirred at room temperature for 20-30 min, cooled, and filtered through a 0.22 μm filter to obtain CsI3 precursor solution. 0.03 FA 0.97 PbI3 precursor solution; Or, (Cs) 0.05 MA 0.05 FA 0.9 )Pb(I 0.93 Br 0.07 The preparation method of the precursor solution is as follows: PbI2, CsI, PbBr2, MACl, MABr, and FAI are added to a mixed solvent of DMF and DMSO, stirred at 40–50°C for 1 h, cooled, and filtered through a 0.22 μm filter to prepare (CsI) 0.05 MA 0.05 FA 0.9 )Pb(I 0.93 Br 0.07 )3. Precursor solution.

8. The method for fabricating a perovskite solar cell based on a hydroxylated hole transport layer according to claim 1, characterized in that, In step (4), the electron transport layer is PC. 61 BM and BCP; PC 61 BM is dissolved in chlorobenzene and stirred at room temperature for more than 12 hours to obtain PC. 61 BM solution: Dissolve BCP in isopropanol and heat and stir at 55°C for 0.5–1.5 h to prepare BCP solution; The electron transport layer was fabricated in two steps: first, PC was spin-coated at 1500 rpm. 61 Spin-coat BM solution for 30 s, then heat-anneal at 90–120°C for 10 min; then spin-coat BCP solution at 3000 rpm for 30 s, and heat-anneal at 90–120°C for 3 min.

9. The fabrication method of a perovskite solar cell based on a hydroxyl-rich hole transport layer according to claim 1, characterized in that, In step (5), a metal electrode is prepared using a high-vacuum metal electrode coating machine to construct a perovskite solar cell; wherein, the annealing in step (2) is performed in an air atmosphere, and steps (3), (4) and (5) are all performed in a glove box under a nitrogen atmosphere.

10. A perovskite solar cell based on a hydroxylated hole transport layer, characterized in that, The perovskite solar cell based on a hydroxylated hole transport layer is prepared using any one of claims 1-9.

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