Perovskite solar cell based on WS2 thin film passivation layer and preparation method and application thereof

Abstract

The invention discloses a perovskite solar cell based on a WS2 thin film passivation layer and a preparation method and application thereof, and belongs to the field of new energy. The perovskite solar cell comprises a conductive substrate, a hole transport layer, a self-assembly monomolecular layer, a perovskite light absorption layer, a passivation layer, an electron transport layer and a top electrode layer which are sequentially stacked. And a single-layer WS2 thin film is arranged between the passivation layer and the electron transport layer. The WS2 thin film is arranged, so that the stability and the weather resistance of the cell are improved, and the photoelectric conversion efficiency is remarkably improved by reducing the interface resistance and promoting efficient transmission of electrons; through the synergistic effect with multiple layers of high-performance materials, the comprehensive performance of the perovskite solar cell based on the WS2 thin film passivation layer is greatly improved.

Description

Technical Field

[0001] The present invention relates to the field of new energy technology, and in particular to a perovskite solar cell based on a WS2 thin film passivation layer and a preparation method and application thereof. Background Art

[0002] Perovskite solar cells are solar cells that use perovskite-type organic metal halide semiconductors as light-absorbing materials. As an emerging solar cell, perovskite solar cells are regarded as an important pillar of future clean energy technology due to their excellent photoelectric conversion efficiency and significant cost advantages. However, related research on perovskite solar cells still needs to overcome two key obstacles: one is the problem of electron transfer efficiency between functional layers, and the other is the overall stability challenge of the battery. The low electron transfer efficiency is mainly due to the electron transfer barrier at the interface of each functional layer, which limits the effective collection and transmission of photocurrent, thereby affecting the overall performance of the battery. On the other hand, the stability problem of the battery is mainly attributed to the sensitivity of perovskite materials to environmental factors such as humidity, temperature and light, which can easily lead to structural damage and performance degradation, seriously hindering its long-term reliable operation and commercialization process. Therefore, in order to solve the current technical problems, further research and exploration are still needed. Summary of the invention

[0003] In order to solve the problems of low electron transfer efficiency between functional layers and insufficient battery stability in the prior art of preparing perovskite solar cells, the present invention discloses a perovskite solar cell based on a WS2 thin film passivation layer and a preparation method and application thereof.

[0004] In order to achieve the above object, the present invention provides the following technical solutions: The present invention provides a perovskite solar cell based on a WS2 thin film passivation layer, comprising a conductive substrate, a hole transport layer, a self-assembled monolayer, a perovskite light absorption layer, a passivation layer, a single-layer WS2 thin film, an electron transport layer and a top electrode layer which are stacked in sequence.

[0005] The thickness of the single-layer WS2 film is 0.7 nm.

[0006] The material of the hole transport layer is NiO x , x is 1~1.5.

[0007] The material of the self-assembled monolayer is one or more of MeO-2PACz, 2PACz, Me-4PACz or 4PACz.

[0008] The material of the perovskite light absorbing layer is (FA 0.95 MA 0.05 ) 0.95 Cs 0.05 Pb(I 0.95Br 0.05 )3. The material of the passivation layer is one or more of PEAI or PEAC1.

[0009] The material of the electron transport layer includes TiO2, SnO2 or one of fullerene and fullerene derivatives.

[0010] The material of the conductive substrate is indium tin oxide, and the material of the top electrode layer is one of gold, silver, copper, graphite or amorphous carbon.

[0011] The present invention also provides a method for preparing a perovskite solar cell based on a WS2 thin film passivation layer, comprising: Spin coating a solution including a material of a hole transport layer on a conductive substrate, and annealing after spin coating to obtain a hole transport layer; Spin coating a solution including a self-assembled monomolecular material on the hole transport layer, and annealing after spin coating to form a self-assembled monomolecular layer; Spin coating on self-assembled monolayers includes (FA 0.95 MA 0.05 ) 0.95 Cs 0.05 Pb(I 0.95 Br 0.05 )3, performing two-stage spin coating at different rotation speeds, adding chlorobenzene to the perovskite precursor solution before the end of spin coating, and annealing after spin coating to obtain a perovskite light absorbing layer; Spin coating a solution including a passivation material on the perovskite light absorbing layer, and annealing after spin coating to form a passivation layer; The CVD deposited single-layer WS2 film is brought into contact with the PDMS sheet, the single-layer WS2 film is transferred to the PDMS sheet, the PDMS sheet carrying the single-layer WS2 is brought into contact with the passivation layer, the single-layer WS2 film is deposited on the passivation layer, and then annealed; The electron transport material and the top electrode material are sequentially deposited on the single-layer WS2 film by vacuum evaporation to form an electron transport layer and a top electrode layer, respectively, to constitute a perovskite solar cell.

[0012] The present invention also provides a photovoltaic device, comprising the above-mentioned perovskite solar cell based on the WS2 thin film passivation layer.

[0013] Compared with the prior art, the present invention has the following beneficial effects: The perovskite solar cell based on the WS2 thin film passivation layer of the present invention deposits a single layer of WS2 thin film between the passivation layer and the electron transport layer. The single layer of WS2 thin film can not only effectively isolate the external water vapor due to its excellent physical and chemical stability, significantly improving the weather resistance and long-term stability of the battery, but also its unique two-dimensional layered structure and good electron transmission characteristics promote the efficient transmission of electrons between functional layers and reduce the electron transmission resistance at the interface, thereby comprehensively improving the photoelectric conversion efficiency and stability of the battery. The WS2 thin film not only improves the stability and weather resistance of the battery, but also significantly improves the photoelectric conversion efficiency by reducing the interface resistance and promoting the efficient transmission of electrons. In addition, through the synergistic effect with multi-layer high-performance materials, the comprehensive performance of the perovskite solar cell based on the WS2 thin film passivation layer has been greatly improved.

[0014] The photovoltaic device provided by the present invention adopts a perovskite solar cell based on a WS2 thin film passivation layer, has excellent photoelectric conversion efficiency and stability, and is widely applicable to application scenarios such as photovoltaic power stations and rooftop photovoltaic systems. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] In order to more clearly illustrate the technical solution of the embodiment of the present invention, the following is a brief introduction to the drawings required for use in the present invention: Figure 1 A schematic diagram of a perovskite solar cell based on a WS2 thin film passivation layer of the present invention; Figure 2 This is a stability comparison chart of the perovskite solar cells based on the WS2 thin film passivation layer prepared in Example 1 and Comparative Example 1.

[0016] In the figure, 1. conductive substrate; 2. hole transport layer; 3. self-assembled monolayer; 4. perovskite light absorption layer; 5. passivation layer; 6. single layer WS2 film; 7. electron transport layer; 8. top electrode layer. DETAILED DESCRIPTION

[0017] The present invention will be further described below in conjunction with the accompanying drawings: In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, rather than all of the embodiments. The components of the embodiments of the present invention described and shown in the drawings here can usually be arranged and designed in various different configurations. Therefore, the following detailed description of the embodiments of the present invention provided in the drawings is not intended to limit the scope of the claimed invention, but merely represents selected embodiments of the present invention. Based on the embodiments in the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.

[0018] like Figure 1 As shown, a perovskite solar cell based on a WS2 thin film passivation layer provided by the present invention comprises a conductive substrate 1, a hole transport layer 2, a self-assembled monolayer 3, a perovskite light absorption layer 4, a passivation layer 5, an electron transport layer 7 and a top electrode layer 8 which are stacked in sequence; A single-layer WS2 film 6 is arranged between the passivation layer and the electron transport layer.

[0019] The material of the hole transport layer is nickel oxide (NiO x (x value is 1~1.5) The material of the self-assembled monolayer is one or more of [2-(3,6-dimethoxy-9H-carbazole-9-yl)ethyl]phosphonic acid (MeO-2PACz), (2-(9H-carbazole-9-yl)ethyl)phosphonic acid (2PACz), (4-(3,6-dimethyl-9H-carbazole-9-yl)butyl)phosphonic acid (Me-4PACz) or [4-(9H-carbazole-9-yl)butyl]phosphonic acid (4PACz). Preferably, the material of the self-assembled monolayer is MeO-2PACz.

[0020] The material of the perovskite light absorbing layer includes (FA 0.95 MA 0.05 ) 0.95 Cs 0.05 Pb(I 0.95 Br 0.05 )3. The material of the passivation layer is phenethylamine iodine (PEAI) or phenethylammonium chloride (PEACl), more preferably PEACl.

[0021] The material of the electron transport layer is titanium dioxide (TiO2), tin oxide (SnO2) or fullerene (C 60 ) and a fullerene derivative. Preferably, the material of the electron transport layer is C 60 .

[0022] The material of the top electrode layer is one of gold, silver, copper, graphite or amorphous carbon. Preferably, the material of the top electrode layer is gold.

[0023] The conductive substrate is transparent conductive glass, and the transparent conductive glass is indium tin oxide (FTO).

[0024] The thickness of the single-layer WS2 film is 0.7 nm.

[0025] In an embodiment of the present invention, the thickness of the conductive substrate is 200-400nm, preferably 250-350nm; specifically 290nm, 300nm, 310nm, 320nm, etc. The thickness of the hole transport layer is 20-40nm, preferably 25-35nm; specifically 26nm, 27nm, 28nm, 29nm, 30nm, 31nm, 32nm, 33nm, 34nm or 35nm. The thickness of the self-assembled monolayer is 1-5nm, preferably 1-3nm, and more preferably 1-2nm. The thickness of the perovskite light absorption layer is 300-700nm, preferably 300-500nm, and more preferably 400-500nm. The thickness of the passivation layer is 1-5nm, preferably 1-3nm, and more preferably 1-2nm. The thickness of the electron transport layer is 10-100nm, preferably 20-80nm, more preferably 30-60nm, and most preferably 40-50nm. The thickness of the top electrode is 50-500 nm, preferably 100-400 nm, and more preferably 100-200 nm.

[0026] In the following examples, unless otherwise specified, all materials used can be obtained through common channels; and the test methods adopted are conventional methods in the art.

[0027] Embodiment 1: The method for preparing a perovskite solar cell based on a WS2 thin film passivation layer in this embodiment includes: S1, wash the FTO glass substrate with acetone, isopropanol and deionized water in sequence, blow dry and set aside; S2, spin coating NiO on FTO glass substrate at 3000 rpm x The nanoparticle solution (concentration of 15 mg / mL, solvent is water) was added for 30 seconds, and then annealed at 300 °C for 10 minutes to form a hole transport layer with a thickness of about 30 nm. S3, spin coating MeO-2PACz solution (solvent is isopropanol, MeO-2PACz solution concentration is 0.6 mg / mL) on the hole transport layer at a speed of 3000 rpm for 30 seconds, and then annealing in an environment of 100°C for 10 minutes to form a self-assembled monolayer, the thickness of the self-assembled monolayer is about 2 nm; S4, prepared according to stoichiometric ratio (FA 0.95 MA 0.05 ) 0.95 Cs 0.05 Pb(I 0.95 Br 0.05)3 Perovskite precursor solution (concentration of 1.5 mol / L, solvent DMF:DMSO=4:1), take 100 μl of perovskite precursor solution and spin coat it on the self-assembled monolayer, the first stage of spin coating has a rotation speed of 2000 rpm, spin coating for 10 s, the second stage of spin coating has a rotation speed of 5000, spin coating for 40 s, 15 s before the end of spin coating, quickly add 200 μl of chlorobenzene as anti-solvent, then anneal on a hot stage at 100°C for 30 minutes to form a perovskite light absorbing layer, the thickness of the perovskite light absorbing layer is about 400 nm; S5, spin coating a PEACl passivation solution (PEACl concentration of 0.2 mg / mL) on the perovskite light absorbing layer at a rotation speed of 3000 rpm for 30 seconds, and then annealing on a hot stage at 100°C for 10 minutes to form a passivation layer with a thickness of about 2 nm; S6, using a linear translation stage and a microscope to bring a CVD deposited single-layer WS2 film (the substrate is quartz, and this CVD single-layer WS2 film can be directly purchased on the market, with an area of ​​about 1cm*1cm) into contact with a PDMS sheet and place it for 20 minutes. During the contact process, the PDMS sheet is heated at 80°C to allow the PDMS sheet to be in close contact with the single-layer WS2 film, and then the PDMS sheet is slowly lifted up to transfer the single-layer WS2 film from the quartz substrate to the PDMS sheet. At the same time, using a linear translation stage and a microscope to bring the PDMS sheet carrying the single-layer WS2 film into contact with the passivation layer and place it for 20 minutes, and then the PDMS sheet is slowly lifted up and then annealed at 100°C for 2 hours to enhance the spatial contact between the single-layer WS2 and the passivation layer (enhance the interface charge transfer), and then a single-layer WS2 film can be deposited on the passivation layer. The thickness of the single-layer WS2 film is 0.7nm; S7, C is deposited on a single-layer WS2 film by vacuum evaporation. 60 , forming an electron transport layer, the thickness of the electron transport layer is about 40nm; S8, depositing gold on the electron transport layer by vacuum evaporation to form a top electrode layer, the thickness of the top electrode layer is about 100 nm; the perovskite solar cell of this embodiment is manufactured through the above steps.

[0028] Embodiment 2: S1, wash the FTO glass substrate with acetone, isopropanol and deionized water in sequence, blow dry and set aside; S2, spin coating NiO on FTO glass substrate at 3000 rpm x The nanoparticle solution (concentration of 15 mg / mL, solvent is water) was added for 30 seconds, and then annealed at 300 °C for 10 minutes to form a hole transport layer with a thickness of about 30 nm. S3, spin coating MeO-2PACz solution (solvent is isopropanol, MeO-2PACz solution concentration is 0.6 mg / mL) on the hole transport layer at a speed of 3000 rpm for 30 seconds, and then annealing in an environment of 100°C for 10 minutes to form a self-assembled monolayer, the thickness of the self-assembled monolayer is about 2 nm; S4, prepared according to stoichiometric ratio (FA 0.95 MA 0.05 ) 0.95 Cs 0.05 Pb(I 0.95 Br 0.05 )3 Perovskite precursor solution (concentration of 1.5 mol / L, solvent DMF:DMSO=4:1), take 100 μl of perovskite precursor solution and spin coat it on the self-assembled monolayer, the first stage of spin coating has a rotation speed of 2000 rpm, spin coating for 10 s, the second stage of spin coating has a rotation speed of 5000, spin coating for 40 s, 15 s before the end of spin coating, quickly add 200 μl of chlorobenzene as anti-solvent, then anneal on a hot stage at 100°C for 30 minutes to form a perovskite light absorbing layer, the thickness of the perovskite light absorbing layer is about 400 nm; S5, spin coating a PEACl passivation solution (PEACl concentration is 2 mg / mL) on the perovskite light absorbing layer at a rotation speed of 3000 rpm for 30 seconds, and then annealing on a hot stage at 100°C for 10 minutes to form a passivation layer with a thickness of about 2 nm; S6, using a linear translation stage and a microscope to bring a CVD-deposited single-layer WS2 film (the substrate is quartz, and this CVD single-layer WS2 film can be directly purchased on the market, with an area of ​​about 1cm*1cm) into contact with the PDMS sheet and leave it there for 20 minutes. During the contact process, the PDMS sheet is heated at 80°C to allow the PDMS sheet to be in close contact with the single-layer WS2 film, and then the PDMS sheet is slowly lifted up to transfer the single-layer WS2 film from the quartz substrate to the PDMS sheet. At the same time, using a linear translation stage and a microscope to bring the PDMS sheet carrying the single-layer WS2 film into contact with the passivation layer and leave it there for 20 minutes, and then the PDMS sheet is slowly lifted up, and then annealed at 100°C for 2 hours to deposit a single-layer WS2 film on the passivation layer. The thickness of the single-layer WS2 film is 0.7nm. S7, C is deposited on a single-layer WS2 film by vacuum evaporation. 60 , forming an electron transport layer, the thickness of the electron transport layer is about 40nm; S8, depositing gold on the electron transport layer by vacuum evaporation to form a top electrode layer, the thickness of the top electrode layer is about 200 nm; the perovskite solar cell of this embodiment is manufactured through the above steps.

[0029] Embodiment 3: S1, wash the FTO glass substrate with acetone, isopropanol and deionized water in sequence, blow dry and set aside; S2, spin coating NiO on FTO glass substrate at 3000 rpm x The nanoparticle solution (concentration of 15 mg / mL, solvent is water) was added for 30 seconds, and then annealed at 300 °C for 10 minutes to form a hole transport layer with a thickness of about 30 nm. S3, spin coating MeO-2PACz solution (solvent is isopropanol, MeO-2PACz solution concentration is 0.6 mg / mL) on the hole transport layer at a speed of 3000 rpm for 30 seconds, and then annealing in an environment of 100°C for 10 minutes to form a self-assembled monolayer, the thickness of the self-assembled monolayer is about 2 nm; S4, prepared according to stoichiometric ratio (FA 0.95 MA 0.05 ) 0.95 Cs 0.05 Pb(I 0.95 Br 0.05 )3 Perovskite precursor solution (concentration of 1.5 mol / L, solvent DMF:DMSO=4:1), take 100 μl of perovskite precursor solution and spin coat it on the self-assembled monolayer, the first stage of spin coating has a rotation speed of 2000 rpm, spin coating for 10 s, the second stage of spin coating has a rotation speed of 5000, spin coating for 40 s, 15 s before the end of spin coating, quickly add 200 μl of chlorobenzene as anti-solvent, then anneal on a hot stage at 100°C for 30 minutes to form a perovskite light absorbing layer, the thickness of the perovskite light absorbing layer is about 400 nm; S5, spin coating PEAI passivation solution (PEAI concentration is 0.5 mg / mL) on the perovskite light absorbing layer at a rotation speed of 3000 rpm for 30 seconds, and then annealing on a hot stage at 100 °C for 10 minutes to form a passivation layer with a thickness of about 2 nm; S6, using a linear translation stage and a microscope to bring a CVD-deposited single-layer WS2 film (the substrate is quartz, and this CVD single-layer WS2 film can be directly purchased on the market, with an area of ​​about 1cm*1cm) into contact with the PDMS sheet and leave it there for 20 minutes. During the contact process, the PDMS sheet is heated at 80°C to allow the PDMS sheet to be in close contact with the single-layer WS2 film, and then the PDMS sheet is slowly lifted up to transfer the single-layer WS2 film from the quartz substrate to the PDMS sheet. At the same time, using a linear translation stage and a microscope to bring the PDMS sheet carrying the single-layer WS2 film into contact with the passivation layer and leave it there for 20 minutes, and then the PDMS sheet is slowly lifted up, and then annealed at 100°C for 2 hours to deposit a single-layer WS2 film on the passivation layer. The thickness of the single-layer WS2 film is 0.7nm. S7, TiO2 is deposited on the single-layer WS2 film by vacuum evaporation to form an electron transport layer, and the thickness of the electron transport layer is about 50nm; S8, depositing gold on the electron transport layer by vacuum evaporation to form a top electrode layer, the thickness of the top electrode layer is about 100 nm; the perovskite solar cell of this embodiment is manufactured through the above steps.

[0030] Embodiment 4: S1, wash the FTO glass substrate with acetone, isopropanol and deionized water in sequence, blow dry and set aside; S2, spin coating NiO on FTO glass substrate at 3000 rpm x The nanoparticle solution (concentration of 15 mg / mL, solvent is water) was added for 30 seconds, and then annealed at 300 °C for 10 minutes to form a hole transport layer with a thickness of about 30 nm. S3, spin coating Me-4PACz solution (solvent is isopropanol, Me-4PACz solution concentration is 0.6 mg / mL) on the hole transport layer at a speed of 3000 rpm for 30 seconds, and then annealing in an environment of 100°C for 10 minutes to form a self-assembled monolayer, the thickness of the self-assembled monolayer is about 2 nm; S4, prepared according to stoichiometric ratio (FA 0.95 MA 0.05 ) 0.95 Cs 0.05 Pb(I 0.95 Br 0.05 )3 Perovskite precursor solution (concentration of 1.5 mol / L, solvent DMF:DMSO=4:1), take 100 μl of perovskite precursor solution and spin coat it on the self-assembled monolayer, the first stage of spin coating has a rotation speed of 2000 rpm, spin coating for 10 s, the second stage of spin coating has a rotation speed of 5000, spin coating for 40 s, 15 s before the end of spin coating, quickly add 200 μl of chlorobenzene as anti-solvent, then anneal on a hot stage at 100°C for 30 minutes to form a perovskite light absorbing layer, the thickness of the perovskite light absorbing layer is about 400 nm; S5, spin coating a PEACl passivation solution (PEACl concentration of 0.2 mg / mL) on the perovskite light absorbing layer at a rotation speed of 3000 rpm for 30 seconds, and then annealing on a hot stage at 100°C for 10 minutes to form a passivation layer with a thickness of about 2 nm; S6, using a linear translation stage and a microscope to bring a CVD-deposited single-layer WS2 film (the substrate is quartz, and this CVD single-layer WS2 film can be directly purchased on the market, with an area of ​​about 1cm*1cm) into contact with the PDMS sheet and leave it there for 20 minutes. During the contact process, the PDMS sheet is heated at 80°C to allow the PDMS sheet to be in close contact with the single-layer WS2 film, and then the PDMS sheet is slowly lifted up to transfer the single-layer WS2 film from the quartz substrate to the PDMS sheet. At the same time, using a linear translation stage and a microscope to bring the PDMS sheet carrying the single-layer WS2 film into contact with the passivation layer and leave it there for 20 minutes, and then the PDMS sheet is slowly lifted up, and then annealed at 100°C for 2 hours to deposit a single-layer WS2 film on the passivation layer. The thickness of the single-layer WS2 film is 0.7nm. S7, C is deposited on a single-layer WS2 film by vacuum evaporation. 60 , forming an electron transport layer, the thickness of the electron transport layer is about 40nm; S8, depositing gold on the electron transport layer by vacuum evaporation to form a top electrode layer, the thickness of the top electrode layer is about 100 nm; the perovskite solar cell of this embodiment is manufactured through the above steps.

[0031] Comparative Example 1: The preparation method of the calcium perovskite solar cell based on the WS2 thin film passivation layer in this comparative example includes: S1, wash the FTO glass substrate with acetone, isopropanol and deionized water in sequence, blow dry and set aside; S2, NiO was deposited on FTO glass substrate by magnetron sputtering x , and then annealed in an environment of 300°C for 10 minutes to form a hole transport layer with a thickness of about 20 nm; S3, spin coating an aluminum oxide nanoparticle solution (nanoparticle size 30 nm, concentration 1 mg / mL, solvent is isopropanol) on the hole transport layer at a rotation speed of 5000 rpm for 30 seconds, and then annealing at 100°C for 10 minutes to form a self-assembled monolayer. The thickness of the self-assembled monolayer is about 40 nm. S4, prepared according to stoichiometric ratio (FA 0.95 MA 0.05 ) 0.95 Cs 0.05 Pb(I 0.95 Br 0.05)3 Perovskite precursor solution (concentration of 1.5 mol / L, solvent DMF:DMSO=4:1), take 100 μl of perovskite precursor solution and spin coat it on the self-assembled monolayer, the first stage of spin coating has a rotation speed of 2000 rpm, spin coating for 10 s, the second stage of spin coating has a rotation speed of 5000, spin coating for 40 s, 15 s before the end of spin coating, quickly add 200 μl of chlorobenzene as anti-solvent, then anneal on a hot stage at 100°C for 30 minutes to form a perovskite light absorbing layer, the thickness of the perovskite light absorbing layer is about 400 nm; S5, spin coating a PEACl passivation solution (PEACl concentration of 0.5 mg / mL) on the perovskite light absorbing layer at a rotation speed of 3000 rpm for 30 seconds, and then annealing on a hot stage at 100°C for 10 minutes to form a passivation layer with a thickness of about 2 nm; S6, depositing C on the passivation layer by vacuum evaporation 60 , forming an electron transport layer, the thickness of the electron transport layer is about 40nm; S7, depositing graphite on the electron transport layer by vacuum evaporation to form a top electrode layer, the thickness of the top electrode layer is about 100 nm; the perovskite solar cell of this comparative example is manufactured through the above steps.

[0032] Battery performance test: The performance of the perovskite solar cells prepared in the examples and comparative examples was tested under room temperature using a 3A solar simulator at 100 mW / cm 2 The photoelectric conversion efficiency of the cells prepared in the embodiment and the comparative example was tested under the light intensity of 0.084 cm 2 The test results are shown in Table 1: Table 1

[0033] According to Table 1 and Figure 2 It can be seen that compared with Comparative Example 1, the photoelectric conversion efficiency of the perovskite solar cell of Example 1 is improved, and the stability is obviously improved because Comparative Example 1 does not contain the stability of the single-layer WS2 film.

[0034] The endpoints and any values ​​of the scope disclosed in the present invention are not limited to the precise scope or value, and these scopes or values ​​should be understood to include values ​​close to these scopes or values. For numerical ranges, the endpoint values ​​of each scope, the endpoint values ​​of each scope and the individual point values, and the individual point values ​​can be combined with each other to obtain one or more new numerical ranges, which should be regarded as specifically disclosed in this article. Hereinafter, in principle, each technical solution can be combined with each other to obtain a new technical solution, which should also be regarded as specifically disclosed in this article.

[0035] The above embodiments are only used to illustrate the technical solutions of the present invention rather than to limit the same. Although the present invention has been described in detail with reference to the above embodiments, a person skilled in the art can still modify or make equivalent substitutions to the specific implementations of the present invention. Any modifications or equivalent substitutions that do not depart from the spirit and scope of the present invention are within the scope of protection of the claims of the present invention to be approved.

Claims

1. A perovskite solar cell based on a WS2 thin film passivation layer, characterized in that: It includes a conductive substrate, a hole transport layer, a self-assembled monolayer, a perovskite light absorption layer, a passivation layer, a single-layer WS2 film, an electron transport layer and a top electrode layer which are stacked in sequence.

2. A perovskite solar cell based on a WS2 thin film passivation layer according to claim 1, characterized in that: The thickness of the single-layer WS2 film is 0.7 nm.

3. A perovskite solar cell based on a WS2 thin film passivation layer according to claim 1, characterized in that: The material of the hole transport layer is NiO x , x is 1~1.

5.

4. A perovskite solar cell based on a WS2 thin film passivation layer according to claim 1, characterized in that: The material of the self-assembled monolayer is one or more of MeO-2PACz, 2PACz, Me-4PACz or 4PACz.

5. A perovskite solar cell based on a WS2 thin film passivation layer according to claim 1, characterized in that: The material of the perovskite light absorbing layer is (FA 0.95 MA 0.05 ) 0.95 Cs 0.05 Pb(I 0.95 Br 0.05 )3.

6. A perovskite solar cell based on a WS2 thin film passivation layer according to claim 1, characterized in that: The material of the passivation layer is one or more of PEAI or PEAC1.

7. A perovskite solar cell based on a WS2 thin film passivation layer according to claim 1, characterized in that: The material of the electron transport layer includes TiO2, SnO2 or one of fullerene and fullerene derivatives.

8. A perovskite solar cell based on a WS2 thin film passivation layer according to claim 1, characterized in that: The material of the conductive substrate is indium tin oxide, and the material of the top electrode layer is one of gold, silver, copper, graphite or amorphous carbon.

9. A method for preparing a perovskite solar cell based on a WS2 thin film passivation layer, characterized in that: include: Spin coating a solution of a material including a hole transport layer on a conductive substrate, and annealing after spin coating to obtain a hole transport layer; Spin coating a solution including a self-assembled monomolecular material on the hole transport layer, and annealing after spin coating to form a self-assembled monomolecular layer; Spin coating on self-assembled monolayers includes (FA 0.95 MA 0.05 ) 0.95 Cs 0.05 Pb(I 0.95 Br 0.05 )3, performing two-stage spin coating at different rotation speeds, adding chlorobenzene to the perovskite precursor solution before the end of spin coating, and annealing after spin coating to obtain a perovskite light absorbing layer; Spin coating a solution including a passivation material on the perovskite light absorbing layer, and annealing after spin coating to form a passivation layer; The CVD deposited single-layer WS2 film is brought into contact with the PDMS sheet, the single-layer WS2 film is transferred to the PDMS sheet, the PDMS sheet carrying the single-layer WS2 is brought into contact with the passivation layer, the single-layer WS2 film is deposited on the passivation layer, and then annealed; The electron transport material and the top electrode material are sequentially deposited on the single-layer WS2 film by vacuum evaporation to form an electron transport layer and a top electrode layer, respectively, to constitute a perovskite solar cell.

10. A photovoltaic device, characterized in that: A perovskite solar cell based on a WS2 thin film passivation layer comprising any one of claims 1-8.

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