PACl modified perovskite light absorption layer, PACl modified perovskite solar cell and method

Abstract

The invention provides a PACl modified perovskite light absorption layer, a PACl modified perovskite solar cell and a method, the PACl modified perovskite light absorption layer comprises a perovskite precursor solution composed of a (FA < 0.95 > MA < 0.05 >) < 0.95 > Cs0 < 0.05 > Pb < I < 0.95 > Br < 0.05 >) < 3 > perovskite material and a PACl passivation material, and the PACl modified perovskite light absorption layer is obtained through spin coating and annealing of the perovskite precursor solution. According to the invention, n-propyl ammonium chloride PACl is added into the perovskite precursor solution to modify perovskite, so that the defects in the perovskite material are significantly reduced, and the efficiency of the perovskite solar cell is improved.

Description

Technical Field

[0001] The invention belongs to the technical field of solar cells, and in particular to a PACl-modified perovskite light-absorbing layer, a PACl-modified perovskite solar cell and a method. Background Art

[0002] As the heart of perovskite solar cells, the performance of the perovskite light-absorbing layer directly determines the photoelectric conversion efficiency and long-term stability of the entire battery system. In recent years, through the unremitting efforts of scientific researchers, the research on perovskite light-absorbing layers has achieved remarkable results, especially in improving the photoelectric conversion efficiency. The photoelectric conversion efficiency of small-area single-junction perovskite solar cells under laboratory conditions has jumped to a new height of 26.7%. This breakthrough not only laid a solid foundation for the commercial application of perovskite solar cells, but also greatly stimulated the enthusiasm of scientific researchers to further optimize the perovskite light-absorbing layer.

[0003] However, while pursuing higher photoelectric conversion efficiency, the problems faced by the perovskite light-absorbing layer cannot be ignored. Among them, the stability problem is particularly prominent. The structure and performance of perovskite materials may change significantly under complex and changeable environmental conditions, such as humidity, temperature and light. Long-term exposure to light and humidity may cause decomposition or phase change of perovskite materials, resulting in a sharp drop in battery performance, reduced efficiency and shortened life. This not only limits the widespread application of perovskite solar cells, but also poses severe challenges to their long-term reliability.

[0004] In addition, the defects and impurities that may exist in the perovskite light-absorbing layer are also important factors affecting the performance of the battery. These defects and impurities act as carrier recombination centers, which will greatly reduce the photoelectric conversion efficiency of the battery. At the same time, the ions in the perovskite material may migrate under the action of the electric field, further exacerbating the attenuation of battery performance. These problems not only hinder the further improvement of the performance of perovskite solar cells, but also pose a potential obstacle to their commercialization process.

[0005] Therefore, the importance of optimizing the perovskite light-absorbing layer is self-evident. By improving the composition, structure and preparation process of perovskite materials, not only can the stability and photoelectric conversion efficiency of the perovskite light-absorbing layer be improved, but also the number of defects and impurities can be reduced, and the recombination rate of carriers can be reduced, thereby extending the service life of the battery. This is of great significance for promoting the continuous advancement and commercial application of perovskite solar cell technology.

[0006] In summary, optimizing the perovskite light-absorbing layer is not only the key to improving the performance of perovskite solar cells, but also an important prerequisite for their commercial application. In the future, researchers will continue to work on the optimization of the perovskite light-absorbing layer, in order to achieve more breakthroughs in photoelectric conversion efficiency, stability and long-term reliability, and open up broader prospects for the widespread application of perovskite solar cells. Summary of the invention

[0007] In order to solve the problems existing in the prior art, the present invention proposes a PACl-modified perovskite light absorbing layer, a PACl-modified perovskite solar cell and a method, wherein n-propylammonium chloride (PACl) is added to a perovskite precursor solution to modify the perovskite, thereby significantly reducing the defects in the perovskite material and improving the efficiency of the perovskite solar cell.

[0008] To achieve the above object, the present invention provides the following technical solution: a PACl-modified perovskite light-absorbing layer, comprising (FA 0.95 MA 0.05 ) 0.95 Cs 0.05 Pb(I 0.95 Br 0.05 )3 A perovskite precursor solution composed of a perovskite material and a PACl passivation material is prepared, and the perovskite precursor solution is spin-coated and annealed to obtain a PACl-modified perovskite light-absorbing layer.

[0009] Furthermore, the total thickness of the PACl-modified perovskite light-absorbing layer is 300nm~700nm.

[0010] Furthermore, the perovskite solution with a concentration of 1.5 mol / L is prepared according to a stoichiometric ratio, and the molar fraction of the PACl passivation material in the perovskite solution is 5% to 20%.

[0011] Furthermore, the spin coating is as follows: after the perovskite precursor solution is spin coated on the dielectric layer at a rotation speed of 1500 rpm to 2000 rpm for 10 s, it is spin coated at a rotation speed of 5000 rpm for another 40 s, and 200 μL of chlorobenzene is quickly added dropwise 10 s before the end of the spin coating to obtain the perovskite film.

[0012] Furthermore, the annealing is to anneal the perovskite film at 100° C. for 25 min to 30 min.

[0013] The present invention also provides a PACl-modified perovskite solar cell, comprising the above-mentioned PACl-modified perovskite light-absorbing layer. Specifically, the structure of the cell comprises, from bottom to top, a substrate, a hole transport layer, a dielectric layer, a PACl-modified perovskite light-absorbing layer, an electron transport layer and a metal electrode.

[0014] Furthermore, the substrate is a transparent conductive glass substrate, and the transparent conductive glass is indium tin oxide; the thickness of the substrate is 200nm~400nm; The hole transport layer is selected from at least one of MeO-2PACz, 2PACz, Me-4PACz, and 4PACz, and the thickness of the hole transport layer is 1 nm to 5 nm; The dielectric layer is Al2O3 nanoparticles, and the thickness of the dielectric layer is 30nm~60nm; The electron transport layer is one of TiO2, SnO2, fullerene and fullerene derivatives; the thickness of the electron transport layer is 10nm~100nm; The metal electrode is one of gold, silver, copper, graphite or amorphous carbon, and the thickness of the metal electrode is 50nm~500nm.

[0015] The present invention also provides a method for preparing a PACl-modified perovskite solar cell, which is as follows: After the substrate is pre-treated, a hole transport layer solution is spin-coated on the substrate to form a hole transport layer; Spin coating a dielectric layer solution on the hole transport layer to form a dielectric layer; The perovskite precursor solution is spin-coated on the dielectric layer and annealed to obtain a PACl-modified perovskite light-absorbing layer, wherein the perovskite precursor solution includes (FA 0.95 MA 0.05 ) 0.95 Cs 0.05 Pb(I 0.95 Br 0.05 )3 Perovskite material and PACl passivation material; An electron transport layer and a metal electrode are sequentially prepared on the PACl-modified perovskite light-absorbing layer to obtain a PACl-modified perovskite solar cell.

[0016] Further, a hole transport layer solution with a concentration of 0.3 mg / ml to 1.2 mg / ml is spin-coated on the substrate at a rotation speed of 2000 rpm to 4000 rpm for 30 s to 40 s, and annealed to form a hole transport layer; Spin coating a dielectric layer solution with a concentration of 0.5 mg / ml to 2 mg / ml on the hole transport layer at a rotation speed of 4000 rpm to 6000 rpm for 30 seconds, and annealing to form a dielectric layer; After the perovskite precursor solution was spin-coated on the dielectric layer at a speed of 1500 rpm to 2000 rpm for 10 seconds, it was spin-coated at a speed of 5000 rpm for another 40 seconds. 200 μL of chlorobenzene was quickly added 10 seconds before the end of the spin coating to obtain a perovskite film. The perovskite film was annealed at 100°C for 25 minutes to 30 minutes to form a PACl-modified perovskite light-absorbing layer. The electron transport layer and the metal electrode were prepared in sequence on the PACl-modified perovskite light-absorbing layer by vacuum evaporation to obtain the ACl-modified perovskite solar cell.

[0017] Furthermore, the perovskite precursor solution includes (FA 0.95 MA 0.05 ) 0.95 Cs 0.05 Pb(I 0.95 Br 0.05 )3 Perovskite material and PACl passivation material, the perovskite solution with a concentration of 1.5 mol / L is prepared according to a stoichiometric ratio, and the molar fraction of the PACl passivation material in the perovskite solution is 5%~20%.

[0018] Compared with the prior art, the present invention has at least the following beneficial effects: The present invention provides a PACl-modified perovskite light-absorbing layer. The defects in the perovskite material are "hot spots" for carrier recombination, which will reduce the photoelectric conversion efficiency of the battery. PACl effectively reduces the defect concentration by combining with these defect sites, thereby reducing the recombination of carriers and improving the open circuit voltage and short circuit current of the battery. This modification not only improves the efficiency of the battery, but also enables the battery to maintain higher stability under long-term operation. The addition of PACl not only reduces defects, but also optimizes the transmission path of carriers by adjusting the microstructure of the perovskite material, reducing the loss during the transmission process. This optimization enables the battery to generate more electrical energy under the same lighting conditions, further improving the photoelectric conversion efficiency of the battery.

[0019] The present invention provides a PACl-modified perovskite solar cell. The PACl-modified perovskite solar cell inherits the advantages of high efficiency and low cost of traditional perovskite solar cells, and achieves comprehensive optimization of battery performance by introducing a PACl passivation material. Due to the bulk passivation effect of PACl on the perovskite material, the recombination and transmission losses of carriers are reduced, so that the battery can generate more electric energy under the same lighting conditions. This efficiency improvement not only makes the PACl-modified perovskite solar cell more competitive in the field of energy conversion, but also provides it with a possibility in a wider range of application scenarios. Secondly, the PACl-modified perovskite solar cell performs well in stability. Perovskite materials are prone to performance degradation under long-term operation, and the addition of PACl significantly enhances the stability of the material and extends the service life of the battery. This improvement in stability is crucial for the commercial application of perovskite solar cells because it means less maintenance costs and higher reliability. In addition, the PACl-modified perovskite solar cell also has the advantages of simple preparation process and low cost. Traditional perovskite solar cells require expensive materials and complex process steps in their preparation, while PACl-modified perovskite solar cells simplify the preparation process and reduce costs by introducing cheap PACl passivation materials. This cost-effectiveness improvement makes PACl-modified perovskite solar cells more competitive in the energy market. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 Schematic diagram of the structure of the PACl-modified perovskite solar cell of the present invention; Figure 2 Fluorescence (PL) spectra of perovskite films before and after passivation (the perovskite layer was directly coated on the substrate without other layers).

[0021] In the attached figure: 1, substrate; 2, hole transport layer; 3, dielectric layer; 4, PACl-modified perovskite light-absorbing layer; 5, electron transport layer; 6, metal electrode. DETAILED DESCRIPTION

[0022] The present invention will be further described below in conjunction with the accompanying drawings and specific embodiments.

[0023] The present invention provides a PACl modified perovskite light absorbing layer, wherein the perovskite precursor solution comprises (FA 0.95 MA 0.05 ) 0.95 Cs 0.05 Pb(I 0.95 Br 0.05 )3 Perovskite material and PACl passivation material, spin coating the perovskite precursor solution and annealing to obtain the PACl modified perovskite light absorbing layer.

[0024] Preferably, (FA 0.95 MA 0.05 ) 0.95 Cs 0.05 Pb(I 0.95 Br 0.05 )3The molar fraction of PACl passivation material in the perovskite solution is 5%~20%.

[0025] Preferably, the total thickness of the PACl-modified perovskite light-absorbing layer is 300-700 nm, more preferably 400-500 nm.

[0026] like Figure 1 As shown, the present invention provides a PACl-modified perovskite solar cell, comprising a substrate 1, a hole transport layer 2, a dielectric layer 3, a PACl-modified perovskite light absorbing layer 4, an electron transport layer 5 and a metal electrode 6; Preferably, the substrate is a transparent conductive glass substrate, and the transparent conductive glass is indium tin oxide (FTO); Preferably, the thickness of the substrate is 200-400 nm, preferably 250-350 nm; specifically 290 nm, 300 nm, 310 nm, 320 nm, etc.

[0027] Preferably, the hole transport layer 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, more preferably (2-(3,6-dimethoxy-9H-carbazole-9-yl)ethyl)phosphonic acid MeO-2PACz; Preferably, the thickness of the hole transport layer is 1 nm to 5 nm, preferably 1 nm to 3 nm, and more preferably 1 nm to 2 nm.

[0028] Preferably, the dielectric layer is Al2O3 nanoparticles, and the thickness of the dielectric layer is 30nm~60nm.

[0029] Preferably, the electron transport layer is TiO2, SnO2 or one of fullerene and fullerene derivatives; More preferably, the electron transport layer is C60; Preferably, the thickness of the electron transport layer is 10 nm to 100 nm, preferably 20 nm to 80 nm, more preferably 30 nm to 60 nm, and most preferably 40 nm to 50 nm.

[0030] Preferably, the metal electrode is one of gold, silver, copper, graphite or amorphous carbon; More preferably, the metal electrode is gold; Preferably, the thickness of the metal electrode is 50 nm to 500 nm, preferably 100 nm to 400 nm, and more preferably 100 nm to 200 nm.

[0031] The preparation method of a PACl-modified perovskite solar cell of the present invention is as follows: Step 1: Clean the substrate with acetone, isopropyl alcohol and deionized water in turn, blow dry and set aside.

[0032] Step 2: Spin-coat a hole transport layer solution with a concentration of 0.3 mg / ml to 1.2 mg / ml on the substrate at a rotation speed of 2000 rpm to 4000 rpm for 30 s to 40 s, and anneal for 10 minutes to form a hole transport layer.

[0033] Step 3: Spin-coat a dielectric layer solution with a concentration of 0.5 mg / ml to 2 mg / ml on the hole transport layer at a rotation speed of 4000 rpm to 6000 rpm for 30 seconds, and anneal for 10 minutes to form an Al2O3 dielectric layer with a thickness of 30 nm to 60 nm.

[0034] Step 4: Prepare according to the stoichiometric ratio (FA 0.95 MA 0.05 ) 0.95 Cs 0.05 Pb(I 0.95 Br 0.05 )3 perovskite solution (concentration of 1.5 mol / L, solvent DMF:DMSO=4:1), PACl is added to the solution, the molar fraction is 5% to 20%, preferably 10%, to obtain a perovskite precursor solution; Take 100 μL of the precursor solution and apply it on the dielectric layer. Spin at a speed of 1500 rpm ~2000 rpm for 10 seconds, and then spin at a speed of 5000 rpm for 40 seconds. Quickly add 200 μL of chlorobenzene as an anti-solvent 10 seconds before the end of spin coating. Then anneal the perovskite film at 100 ° C on a hot stage for 25 min ~ 30 min to form a PACl-modified perovskite light-absorbing layer with a thickness of 300 ~ 700 nm.

[0035] Step 5: Prepare an electron transport layer on the PACl-modified perovskite light-absorbing layer using a vacuum evaporation method with a thickness of 10 nm to 100 nm.

[0036] Step 6: Finally, a metal electrode 6 is prepared by vacuum evaporation method with a thickness of 50nm~500nm to obtain a solar cell.

[0037] Example 1 The preparation method of a PACl-modified perovskite solar cell of the present invention is as follows: Step 1: Clean the FTO glass substrate with acetone, isopropanol and deionized water in turn, blow dry and set aside.

[0038] Step 2: Spin-coat a 0.6 mg / mL MeO-2PACz solution (solvent: isopropanol) on the FTO glass substrate at 3000 rpm for 30 seconds and anneal for 10 minutes to form a hole transport layer.

[0039] Step 3: Spin-coat an aluminum oxide nanoparticle solution (nanoparticle size 30 nm, concentration 1 mg / mL, solvent is isopropanol) on the hole transport layer at 5000 rpm for 30 seconds, and anneal for 10 minutes to form an Al2O3 dielectric layer.

[0040] Step 4: Prepare according to the 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 is 1.5 mol / L, solvent is DMF:DMSO=4:1), add PACl in the solution with a molar fraction of 10%, take 100μL of the precursor solution and apply it on the dielectric layer, spin at 2000rpm for 10s, spin at 5000rpm for 40s, quickly add 200μL of chlorobenzene as anti-solvent 10s before the end of spin coating, and then anneal the perovskite film at 100℃ on a hot stage for 30 minutes to form a PACl-modified perovskite light-absorbing layer with a thickness of about 400nm.

[0041] Step 5: Prepare an electron transport layer C on the PACl-modified perovskite light-absorbing layer by vacuum evaporation on the perovskite layer 60 , thickness is about 40nm.

[0042] Step 6. Finally, use vacuum evaporation to prepare metal electrode gold with a thickness of about 100nm to obtain a solar cell.

[0043] Figure 2 The fluorescence (PL) spectrum of the perovskite film before and after passivation (the perovskite layer is directly coated on the substrate without other layers) is used. From the PL results, it can be seen that the PL intensity of the perovskite film increases 10 times after adding PACl to the perovskite precursor, which indicates that the addition of PACl can achieve effective bulk passivation, increase the perovskite grain size, and reduce bulk defects.

[0044] Example 2 The preparation method of a PACl-modified perovskite solar cell of the present invention is as follows: Step 1: Clean the FTO glass substrate with acetone, isopropanol and deionized water in turn, blow dry and set aside.

[0045] Step 2: Spin-coat a 0.6 mg / mL 2PACz solution (solvent: isopropanol) on the FTO glass substrate at 3000 rpm for 30 seconds and anneal for 10 minutes to form a hole transport layer.

[0046] Step 3: Spin-coat an aluminum oxide nanoparticle solution (nanoparticle size 30 nm, concentration 1 mg / mL, solvent is isopropanol) on the hole transport layer at 5000 rpm for 30 seconds, and anneal for 10 minutes to form an Al2O3 dielectric layer.

[0047] Step 4: Prepare according to the 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 is 1.5 mol / L, solvent is DMF:DMSO=4:1), add PACl in the solution with a molar fraction of 10%, take 100μL of the precursor solution and apply it on the dielectric layer, spin at 2000rpm for 10s, spin at 5000rpm for 40s, quickly add 200μL of chlorobenzene as anti-solvent 10s before the end of spin coating, and then anneal the perovskite film at 100℃ on a hot stage for 30 minutes to form a PACl-modified perovskite light-absorbing layer with a thickness of about 400nm.

[0048] Step 5: Prepare an electron transport layer TiO2 on the PACl-modified perovskite light-absorbing layer using a vacuum evaporation method on the perovskite layer, with a thickness of about 40 nm.

[0049] Step 6. Finally, use vacuum evaporation to prepare metal electrode silver with a thickness of about 100nm to obtain a solar cell.

[0050] Example 3 The preparation method of a PACl-modified perovskite solar cell of the present invention is as follows: Step 1: Clean the FTO glass substrate with acetone, isopropanol and deionized water in turn, blow dry and set aside.

[0051] Step 2: Spin-coat a 0.6 mg / mL Me-4PACz solution (solvent: isopropanol) on the FTO glass substrate at 3000 rpm for 30 seconds and anneal for 10 minutes to form a hole transport layer.

[0052] Step 3: Spin-coat an aluminum oxide nanoparticle solution (nanoparticle size 30 nm, concentration 1 mg / mL, solvent is isopropanol) on the hole transport layer at 5000 rpm for 30 seconds, and anneal for 10 minutes to form an Al2O3 dielectric layer.

[0053] Step 4: Prepare according to the 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 is 1.5 mol / L, solvent is DMF:DMSO=4:1), add PACl in the solution with a molar fraction of 10%, take 100μL of the precursor solution and apply it on the dielectric layer, spin at 2000rpm for 10s, spin at 5000rpm for 40s, quickly add 200μL of chlorobenzene as anti-solvent 10s before the end of spin coating, and then anneal the perovskite film at 100℃ on a hot stage for 30 minutes to form a PACl-modified perovskite light-absorbing layer with a thickness of about 400nm.

[0054] Step 5: Prepare an electron transport layer SnO2 on the PACl-modified perovskite light-absorbing layer using a vacuum evaporation method on the perovskite layer, with a thickness of about 40 nm.

[0055] Step 6: Finally, a metal electrode copper is prepared by vacuum evaporation method with a thickness of about 100 nm to obtain a solar cell.

[0056] Example 4 The preparation method of a PACl-modified perovskite solar cell of the present invention is as follows: Step 1: Clean the FTO glass substrate with acetone, isopropanol and deionized water in turn, blow dry and set aside.

[0057] Step 2: Spin-coat a 0.6 mg / mL 4PACz solution (solvent: isopropanol) on the FTO glass substrate at 3000 rpm for 30 seconds and anneal for 10 minutes to form a hole transport layer.

[0058] Step 3: Spin-coat an aluminum oxide nanoparticle solution (nanoparticle size 30 nm, concentration 1 mg / mL, solvent is isopropanol) on the hole transport layer at 5000 rpm for 30 seconds, and anneal for 10 minutes to form an Al2O3 dielectric layer.

[0059] Step 4: Prepare according to the 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 is 1.5 mol / L, solvent is DMF:DMSO=4:1), add PACl in the solution with a molar fraction of 10%, take 100μL of the precursor solution and apply it on the dielectric layer, spin at 2000rpm for 10s, spin at 5000rpm for 40s, quickly add 200μL of chlorobenzene as anti-solvent 10s before the end of spin coating, and then anneal the perovskite film at 100℃ on a hot stage for 30 minutes to form a PACl-modified perovskite light-absorbing layer with a thickness of about 400nm.

[0060] Step 5: Prepare an electron transport layer fullerene on the PACl-modified perovskite light-absorbing layer using a vacuum evaporation method on the perovskite layer, with a thickness of about 40 nm.

[0061] Step 6. Finally, a metal electrode graphite is prepared by vacuum evaporation method with a thickness of about 100 nm to obtain a solar cell.

[0062] Example 5 The preparation method of a PACl-modified perovskite solar cell of the present invention is as follows: Step 1: Clean the FTO glass substrate with acetone, isopropanol and deionized water in turn, blow dry and set aside.

[0063] Step 2: Spin-coat 0.6 mg / mL 4PACz and MeO-2PACz solution (solvent is isopropanol) on the FTO glass substrate at 3000 rpm for 30 seconds and anneal for 10 minutes to form a hole transport layer.

[0064] Step 3: Spin-coat an aluminum oxide nanoparticle solution (nanoparticle size 30 nm, concentration 1 mg / mL, solvent is isopropanol) on the hole transport layer at 5000 rpm for 30 seconds, and anneal for 10 minutes to form an Al2O3 dielectric layer.

[0065] Step 4: Prepare according to the 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 is 1.5 mol / L, solvent is DMF:DMSO=4:1), add PACl in the solution with a molar fraction of 10%, take 100μL of the precursor solution and apply it on the dielectric layer, spin at 2000rpm for 10s, spin at 5000rpm for 40s, quickly add 200μL of chlorobenzene as anti-solvent 10s before the end of spin coating, and then anneal the perovskite film at 100℃ on a hot stage for 30 minutes to form a PACl-modified perovskite light-absorbing layer with a thickness of about 400nm.

[0066] Step 5: Prepare the electron transport layer C60 and fullerene on the PACl-modified perovskite light-absorbing layer by vacuum evaporation on the perovskite layer, with a thickness of about 40 nm.

[0067] Step 6. Finally, amorphous carbon is prepared on the metal electrode by vacuum evaporation with a thickness of about 100 nm to obtain a solar cell.

[0068] Example 6 The preparation method of a PACl-modified perovskite solar cell of the present invention is as follows: Step 1: Clean the FTO glass substrate with acetone, isopropanol and deionized water in turn, blow dry and set aside.

[0069] Step 2: Spin-coat 0.6 mg / mL 4PACz and MeO-2PACz solution (solvent is isopropanol) on the FTO glass substrate at 3000 rpm for 30 seconds and anneal for 10 minutes to form a hole transport layer with a thickness of .

[0070] Step 3: Spin-coat an aluminum oxide nanoparticle solution (nanoparticle size 30 nm, concentration 1 mg / mL, solvent is isopropanol) on the hole transport layer at 5000 rpm for 30 s, and anneal for 10 minutes to form an Al2O3 dielectric layer with a thickness of .

[0071] Step 4: Prepare according to the 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 1.5 mol / L, solvent DMF:DMSO=4:1), PACl was added to the solution with a molar fraction of 10%; 100 μL of the precursor solution was applied on the dielectric layer, with a rotation speed of 2000 rpm for 10 s, and a rotation speed of 5000 for 40 s. 200 μL of chlorobenzene was quickly added as an anti-solvent 10 s before the end of spin coating. The perovskite film was then annealed on a hot stage at 100 °C for 30 min to form a PACl-modified perovskite light-absorbing layer with a thickness of approximately 300 nm.

[0072] Step 5: Prepare an electron transport layer C60 and fullerene on the PACl-modified perovskite light-absorbing layer by vacuum evaporation on the perovskite layer, with a thickness of about 40 nm.

[0073] Step 6. Finally, amorphous carbon is prepared on the metal electrode by vacuum evaporation with a thickness of about 100 nm to obtain a solar cell.

[0074] Example 7 The preparation method of a PACl-modified perovskite solar cell of the present invention is as follows: Step 1: Clean the FTO glass substrate with acetone, isopropanol and deionized water in turn, blow dry and set aside.

[0075] Step 2: Spin-coat 0.6 mg / mL 4PACz and MeO-2PACz solution (solvent is isopropanol) on the FTO glass substrate at 3000 rpm for 30 seconds and anneal for 10 minutes to form a hole transport layer with a thickness of .

[0076] Step 3: Spin-coat an aluminum oxide nanoparticle solution (nanoparticle size 30 nm, concentration 1 mg / mL, solvent is isopropanol) on the hole transport layer at 5000 rpm for 30 s, and anneal for 10 minutes to form an Al2O3 dielectric layer with a thickness of .

[0077] Step 4: Prepare according to the 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 1.5 mol / L, solvent DMF:DMSO=4:1), PACl was added to the solution with a molar fraction of 10%; 100 μL of the precursor solution was applied on the dielectric layer, with a rotation speed of 2000 rpm for 10 s, and a rotation speed of 5000 for 40 s. 200 μL of chlorobenzene was quickly added as an anti-solvent 10 s before the end of spin coating, and then the perovskite film was annealed at 100 °C on a hot stage for 30 min to form a PACl-modified perovskite light-absorbing layer with a thickness of about 700 nm.

[0078] Step 5: Prepare the electron transport layer C60 and fullerene on the PACl-modified perovskite light-absorbing layer by vacuum evaporation on the perovskite layer, with a thickness of about 40 nm.

[0079] Step 6. Finally, amorphous carbon is prepared on the metal electrode by vacuum evaporation with a thickness of about 100 nm to obtain a solar cell.

[0080] Comparative Example: A method for preparing a perovskite solar cell, the specific steps are as follows: Step 1: Clean the FTO glass substrate with acetone, isopropanol and deionized water in turn, blow dry and set aside.

[0081] Step 2: Spin-coat a 0.6 mg / mL MeO-2PACz solution (solvent: isopropanol) on the FTO glass substrate at 3000 rpm for 30 seconds and anneal for 10 minutes to form a hole transport layer.

[0082] Step 3: Spin-coat an aluminum oxide nanoparticle solution (nanoparticle size 30 nm, concentration 1 mg / mL, solvent is isopropanol) on the hole transport layer at 5000 rpm for 30 seconds, and anneal for 10 minutes to form an Al2O3 dielectric layer.

[0083] Step 4: Prepare according to the 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 is 1.5mol / L, solvent is DMF:DMSO=4:1), take 100μL of precursor solution and apply it on the dielectric layer, spin coating at 2000rpm for 10s, spin coating at 5000rpm for 40s, quickly add 200μL of chlorobenzene as anti-solvent 15s before the end of spin coating, and then anneal the perovskite film at 100℃ on a hot stage for 30 minutes to form a perovskite light-absorbing layer with a thickness of about 400nm.

[0084] Step 5: Prepare an electron transport layer C60 on the passivation layer by vacuum evaporation on the perovskite layer, with a thickness of about 40 nm.

[0085] Step 6. Finally, use vacuum evaporation to prepare metal electrode gold with a thickness of about 100nm to obtain a solar cell.

[0086] The performance of the solar cells prepared in Example 1 and Comparative Example 1 was tested. Under room temperature, a 3A solar simulator was used to test the performance of the solar cells at 100 mW / cm 2 The conversion efficiency of the top and bottom cells prepared in the examples and comparative examples was tested under light intensity. The effective area of ​​the cell was 0.084 cm 2 , the battery test results are as follows: Table 1 Test results of batteries prepared in Example 1

[0087] Table 2 Comparative Example Preparation Bottom Cell Performance Test Results

[0088] From the battery test results in Table 1 and Table 2, it can be seen that the battery performance prepared in Example 1 is significantly improved compared with the control example, which indicates that the introduction of PACl into the perovskite precursor helps to increase the perovskite grain size, reduce bulk defects, and improve battery performance.

Claims

1. A PACl-modified perovskite light-absorbing layer, characterized in that: Includes (FA 0.95 MA 0.05 ) 0.95 Cs 0.05 Pb(I 0.95 Br 0.05 )3 A perovskite precursor solution composed of a perovskite material and a PACl passivation material is prepared, and the perovskite precursor solution is spin-coated and annealed to obtain a PACl-modified perovskite light-absorbing layer.

2. The PACl-modified perovskite light-absorbing layer according to claim 1, characterized in that: The total thickness of the PACl-modified perovskite light-absorbing layer is 300nm~700nm.

3. The PACl-modified perovskite light-absorbing layer according to claim 1, characterized in that: The perovskite solution with a concentration of 1.5 mol / L is prepared according to a stoichiometric ratio, and the molar fraction of the PACl passivation material in the perovskite solution is 5% to 20%.

4. The PACl-modified perovskite light-absorbing layer according to claim 1, characterized in that: The spin coating is as follows: after the perovskite precursor solution is spin coated on the dielectric layer at a rotation speed of 1500 rpm to 2000 rpm for 10 seconds, the perovskite precursor solution is spin coated at a rotation speed of 5000 rpm for another 40 seconds, and 200 μL of chlorobenzene is quickly added dropwise 10 seconds before the end of the spin coating to obtain the perovskite film.

5. The PACl-modified perovskite light-absorbing layer according to claim 4, characterized in that: The annealing is to anneal the perovskite film at 100° C. for 25 min to 30 min.

6. A PACl-modified perovskite solar cell, characterized in that: The battery comprises the PACl-modified perovskite light-absorbing layer according to any one of claims 1 to 5, wherein the structure of the battery comprises, from bottom to top, a substrate (1), a hole transport layer (2), a dielectric layer (3), a PACl-modified perovskite light-absorbing layer (4), an electron transport layer (5) and a metal electrode (6).

7. A PACl-modified perovskite solar cell according to claim 6, characterized in that: The substrate (1) is a transparent conductive glass substrate, and the transparent conductive glass is indium tin oxide; the thickness of the substrate (1) is 200 nm to 400 nm; The hole transport layer (2) is selected from at least one of MeO-2PACz, 2PACz, Me-4PACz and 4PACz, and the thickness of the hole transport layer (2) is 1 nm to 5 nm; The dielectric layer (3) is Al2O3 nanoparticles, and the thickness of the dielectric layer (3) is 30nm-60nm; The electron transport layer (5) is one of TiO2, SnO2, fullerene and fullerene derivatives; the thickness of the electron transport layer (5) is 10nm~100nm; The metal electrode (6) is one of gold, silver, copper, graphite or amorphous carbon, and the thickness of the metal electrode (6) is 50 nm to 500 nm.

8. The method for preparing a PACl-modified perovskite solar cell according to claim 6 or 7, characterized in that: The details are as follows: After the substrate (1) is pre-treated, a hole transport layer solution is spin-coated on the substrate (1) to form a hole transport layer (2); Spin coating a dielectric layer solution on the hole transport layer (2) to form a dielectric layer (3); A perovskite precursor solution is spin-coated on the dielectric layer (3), and annealed to obtain a PACl-modified perovskite light-absorbing layer (4), wherein the perovskite precursor solution includes (FA 0.95 MA 0.05 ) 0.95 Cs 0.05 Pb(I 0.95 Br 0.05 )3 Perovskite material and PACl passivation material; An electron transport layer (5) and a metal electrode (6) are sequentially prepared on the PACl-modified perovskite light-absorbing layer (4) to obtain a PACl-modified perovskite solar cell.

9. The method for preparing a PACl-modified perovskite solar cell according to claim 8, characterized in that: Spin coating a hole transport layer solution with a concentration of 0.3 mg / ml to 1.2 mg / ml on the substrate (1) at a rotation speed of 2000 rpm to 4000 rpm for 30 s to 40 s, and annealing to form a hole transport layer (2); Spin coating a dielectric layer solution with a concentration of 0.5 mg / ml to 2 mg / ml on the hole transport layer (2) at a rotation speed of 4000 rpm to 6000 rpm for 30 seconds, and annealing to form a dielectric layer (3); After the perovskite precursor solution is spin-coated on the dielectric layer (3) at a speed of 1500 rpm to 2000 rpm for 10 seconds, it is spin-coated at a speed of 5000 rpm for another 40 seconds. 200 μL of chlorobenzene is quickly added dropwise 10 seconds before the end of the spin coating to obtain a perovskite film. The perovskite film is annealed at 100° C. for 25 minutes to 30 minutes to form a PACl-modified perovskite light-absorbing layer (4); An electron transport layer (5) and a metal electrode (6) are sequentially prepared on a PACl-modified perovskite light-absorbing layer (4) by a vacuum evaporation method to obtain an ACl-modified perovskite solar cell.

10. The method for preparing a PACl-modified perovskite solar cell according to claim 8 or 9, characterized in that: The perovskite precursor solution includes (FA 0.95 MA 0.05 ) 0.95 Cs 0.05 Pb(I 0.95 Br 0.05 )3 Perovskite material and PACl passivation material, the perovskite solution with a concentration of 1.5 mol / L is prepared according to a stoichiometric ratio, and the molar fraction of the PACl passivation material in the perovskite solution is 5%~20%.

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