Bulk phase passivation perovskite light absorption layer, solar cell and preparation method

Abstract

The invention relates to the technical field of perovskite solar cell preparation, in particular to a bulk phase passivation perovskite light absorption layer, a solar cell and a preparation method, the bulk phase passivation perovskite light absorption layer is prepared by adopting a perovskite layer prefabricated liquid, the perovskite layer prefabricated liquid comprises (FA 0.95 MA0.05) 0.95 Cs0.05 Pb (I 0.95 Br0.05) 3 and m-F-PEACl, the molar concentration ratio of the (FA 0.95 MA0.05) 0.95 Cs0.05 Pb (I 0.95 Br0.05) 3 to the m-F-PEACl is 1.5: (0.1-1), m-F-PEACl and (FA < 0.95 > MA0. 05) < 0.95 > Cs0. 05Pb (I < 0.95 > Br0. 05) 3 are matched to form a bulk phase passivated perovskite layer, so that organic cations in the m-F-PEACl interact with uncoordinated lead ions or other defect sites in the (FA < 0.95 > MA0. 05) < 0.95 > Cs0. 05Pb (I < 0.95 > Br0. 05) 3 to form a stable complex or compound, the defect concentration in perovskite is reduced, comprehensive and effective passivation is realized, and the performance of the perovskite is improved. Therefore, the photoelectric property and the stability of the perovskite material are improved. The problem that comprehensive and effective passivation cannot be achieved through a perovskite thin film passivation method in the prior art is solved.

Description

Technical Field

[0001] The present invention relates to the technical field of perovskite solar cell preparation, and in particular to a bulk passivation perovskite light-absorbing layer, a solar cell and a preparation method thereof. Background Art

[0002] With the development of society, our demand for energy is increasing day by day. However, the fossil energy available to us is becoming increasingly depleted, and the world is facing a serious energy crisis. In recent years, research on new energy sources has become increasingly popular, including solar energy, wind energy, geothermal energy, tidal energy, etc. Among them, solar energy has the advantages of being inexhaustible. The rational and efficient use of solar energy can solve the current energy crisis. At present, perovskite solar cells have become a research hotspot for new solar cells because of their outstanding advantages such as high energy conversion efficiency, light weight, low cost, simple manufacturing process, flexible devices, and easy large-scale production.

[0003] The research on perovskite solar cells began in 2009. Scientists used perovskite materials CH3NH3PbI3 and CH3NH3PbBr3 as sensitizers in dye-sensitized solar cells for the first time and achieved a photoelectric conversion efficiency of about 4%. This exciting result paved the way for the development of a new topic at the forefront of current research - high-efficiency perovskite photovoltaic technology. With the unremitting efforts of scientists, it took more than ten years to go through the sixty-year efficiency improvement of crystalline silicon cells. The new generation of solar cells based on perovskites are showing a bright application prospect.

[0004] The perovskite light-absorbing layer in the perovskite solar cell device is the place where the photogenerated excitons separate. The quality of the perovskite film seriously affects the photoelectric performance of the perovskite solar cell. The defects of the perovskite film will directly lead to the deterioration of the perovskite crystal quality and the energy level matching between the layers, thereby increasing the probability of carrier capture and recombination by defects, reducing the efficiency of charge transfer, and accelerating the decomposition of perovskite, resulting in reduced battery efficiency and stability. The existing technology usually adopts the method of surface passivation to improve the defects on the surface of the perovskite light-absorbing layer. For example: the Chinese invention with publication number CN115548219A discloses a passivation method for a perovskite film layer and a prepared perovskite solar cell, wherein the passivation method adopts coating the perovskite film layer with any one or a combination of at least two of phenylethyl ammonium iodide solution, o-fluorophenylethylamine iodide solution, n-butylamine iodine solution or dibutylamine iodine solution, annealing, and obtaining a 2-dimensional perovskite passivation layer; coating the 2-dimensional perovskite passivation layer with octylamine iodide solution and / or heptylamine iodide solution, annealing, and obtaining a second passivation layer. The hydrophobicity of the surface of the perovskite film is improved through the synergy of the two passivation layer solutions, and the iodine vacancies in the perovskite can be filled, thereby achieving the effect of passivating the perovskite film layer and improving the efficiency of the perovskite solar cell. The Chinese invention with publication number CN117998878A discloses a passivation layer modified inverse perovskite solar cell and a preparation method thereof, which relates to the technical field of interface modification of perovskite solar cells, and by arranging a passivation layer between a perovskite layer and an electron transport layer, the passivation layer comprises a first passivation layer arranged on the perovskite layer and a second passivation layer arranged on the first passivation layer; wherein the first passivation layer comprises a PEAI layer, the PEAI layer comprises 2-phenylethylamine hydroiodide; the second passivation layer comprises at least one of an OAI layer and an ADP layer, the OAI layer comprises octyl iodide ammonium, and the ADP layer comprises 2-amidinopyridine hydrochloride. To achieve the purpose of reducing the surface defects of the perovskite layer and improving the photoelectric conversion efficiency of the perovskite solar cell.

[0005] However, perovskite films inherently have a large number of surface and bulk defects. The presence of defects will capture photogenerated carriers and reduce the efficiency of the cell. Therefore, the photovoltaic parameters of perovskite solar cells are closely related to the recombination of photogenerated carriers inside the perovskite or at surface defects. The above-mentioned passivation methods are passivation on the surface of the perovskite film, which cannot achieve comprehensive and effective passivation. Summary of the invention

[0006] In view of the problem that the perovskite thin film passivation method in the prior art cannot achieve comprehensive and effective passivation, the present invention provides a bulk passivated perovskite light absorbing layer, a solar cell and a preparation method.

[0007] In order to achieve the above object, the present invention adopts the following technical solutions: The present invention provides a bulk passivated perovskite light absorbing layer, which is prepared by using a perovskite layer prefabricated solution, wherein the perovskite layer prefabricated solution comprises (FA 0.95 MA 0.05 ) 0.95 Cs 0.05 Pb(I 0.95 Br 0.05 )3 and mF-PEACl.

[0008] Furthermore, the solvent of the perovskite layer prefabricated solution is a mixture of DMF and DMSO.

[0009] Furthermore, the volume ratio of DMF to DMSO is 4:1.

[0010] The present invention provides a perovskite solar cell, comprising a substrate and the above-mentioned bulk passivated perovskite light-absorbing layer; A hole transport layer, a dielectric layer, an electron transport layer and a top electrode are sequentially arranged on the substrate; The bulk passivation perovskite light absorbing layer is arranged between the dielectric layer and the electron transport layer.

[0011] Furthermore, the substrate is indium tin oxide conductive glass, and the thickness of the substrate is 200-400 nm.

[0012] Furthermore, the hole transport layer is one or more of MeO-2PACz, 2PACz, Me-4PACz and 4PACz, and the thickness of the hole transport layer is 1 to 5 nm.

[0013] Furthermore, the dielectric layer is Al2O3 nanoparticles, and the thickness of the dielectric layer is 30-60 nm.

[0014] Furthermore, the thickness of the bulk passivated perovskite light-absorbing layer is 300 to 700 nm; the electron transport layer is one of TiO2, SnO2, fullerene and a fullerene derivative, and the thickness of the electron transport layer is 10 to 100 nm.

[0015] Furthermore, the top electrode is one of gold, silver, copper, graphite and amorphous carbon, and the thickness of the top electrode is 50-500 nm.

[0016] The present invention also provides a method for preparing the above-mentioned perovskite solar cell, comprising: preparing a hole transport layer on a substrate; preparing a dielectric layer on the hole transport layer; preparing a bulk passivated perovskite light absorbing layer on the dielectric layer; preparing an electron transport layer on the phase-passivated perovskite light-absorbing layer; A top electrode is prepared on the electron transport layer to complete the preparation of the perovskite solar cell.

[0017] Compared with the prior art, the present invention has the following beneficial effects: The present invention discloses a bulk phase passivated perovskite light absorbing layer, wherein the bulk phase passivated perovskite light absorbing layer is prepared by using a perovskite layer prefabricated solution, wherein the perovskite layer prefabricated solution comprises (FA 0.95 MA 0.05 ) 0.95 Cs 0.05 Pb(I 0.95 Br 0.05 )3 and m-fluorophenylethylamine chloride (mF-PEACl). By using mF-PEACl as a passivating agent with (FA 0.95 MA 0.05 ) 0.95 Cs 0.05 Pb(I 0.95 Br 0.05 )3 to form a bulk passivated perovskite layer. The organic cations in mF-PEACl can react with (FA 0.95 MA 0.05 ) 0.95 Cs 0.05 Pb(I 0.95 Br 0.05 )3 interacts with the uncoordinated lead ions or other defect sites to form a stable complex or composite. This interaction reduces the defect concentration inside the perovskite, especially those defects that can capture carriers and cause non-radiative recombination, achieving comprehensive and effective passivation; the photoelectric performance and stability of the perovskite material are effectively improved; at the same time, mF-PEACl and (FA 0.95 MA 0.05 ) 0.95 Cs 0.05 Pb(I 0.95 Br 0.05 )3, which effectively improves the open circuit voltage and fill factor, effectively reduces the defects in the perovskite film layer, improves the battery efficiency, and prevents passivation from forming an insulating layer that affects the transfer of charges.

[0018] The present invention also provides a perovskite solar cell, comprising a substrate and the above-mentioned bulk passivation perovskite light-absorbing layer; the perovskite solar cell has higher energy conversion efficiency, and is characterized by light weight, long life and low cost.

[0019] The substrate is indium tin oxide conductive glass (FTO), and the thickness of the substrate is 200 to 400 nm. The resistivity of FTO conductive glass can be very low, reaching one ten-thousandth of an ohm-meter level, which enables it to effectively transmit current in electronic devices and ensure the effective transmission of electrons in perovskite solar cells in the device.

[0020] The hole transport layer is MeO-2PACz ((2-(3,6-dimethoxy-9H-carbazole-9-yl)ethyl)phosphonic acid, C 16 H 18 NO5P), 2PACz (2-amino-3-carboxyquinoline, C9H8N2O2), Me-4PACz ([4-(3,6-dimethyl-9H-carbazol-9-yl)butyl]phosphoric acid, C 18 H 22 NO3P) and 4PACz ([4-(9H-carbazol-9-yl)butyl]phosphonic acid, C 16 H 18 NO3P), the thickness of the hole transport layer is 1 to 5 nm, which can effectively reduce the non-radiative recombination between the hole transport layer and the perovskite interface, which helps to improve the photoelectric conversion efficiency of the solar cell.

[0021] The dielectric layer is Al2O3 nanoparticles, and the thickness of the dielectric layer is 30-60nm. The Al2O3 nanoparticles have a very high resistivity, which can effectively isolate the current between different layers, prevent the occurrence of short circuit and leakage, and are corrosion-resistant and have good mechanical properties.

[0022] The electron transport layer is one of TiO2, SnO2, fullerene and fullerene derivatives, which can quickly guide the photogenerated electrons generated by the perovskite layer, reduce electron recombination, and thus improve the photoelectric conversion efficiency.

[0023] The top electrode is one of gold, silver, copper, graphite and amorphous carbon, which can ensure efficient transmission of electrons.

[0024] The present invention also provides a method for preparing the above-mentioned perovskite solar cell. The method realizes the preparation of the perovskite solar cell by sequentially preparing a hole transport layer, a dielectric layer, a bulk passivated perovskite light absorbing layer, an electron transport layer and a top electrode on a substrate. The method is simple and easy to industrialize on a large scale. The prepared perovskite solar cell has high energy conversion efficiency, light weight, long life and low cost. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 It is a schematic diagram of the structure of the perovskite solar cell of the present invention.

[0026] Figure 2The present invention is a flow chart of the method for preparing a perovskite solar cell.

[0027] 1-substrate, 2-hole transport layer, 3-dielectric layer, 4-bulk passivated perovskite light absorbing layer, 5-electron transport layer, 6-top electrode. DETAILED DESCRIPTION

[0028] In order to enable those skilled in the art to understand the characteristics and effects of the present invention, the following is a general description and definition of the terms and expressions mentioned in the specification and claims. Unless otherwise specified, all technical and scientific terms used in the text are the common meanings understood by those skilled in the art for the present invention. In the event of a conflict, the definition in this specification shall prevail.

[0029] The theories or mechanisms described and disclosed herein, whether correct or incorrect, should not limit the scope of the present invention in any way, that is, the present invention can be implemented without being limited by any specific theory or mechanism.

[0030] In this article, all features such as values, quantities, contents and concentrations defined in the form of numerical ranges or percentage ranges are for simplicity and convenience only. Accordingly, the description of numerical ranges or percentage ranges should be considered to have included and specifically disclosed all possible secondary ranges and individual values ​​within the range (including integers and fractions).

[0031] In this document, unless otherwise specified, “includes,” “including,” “contains,” “has,” or similar terms cover the meanings of “consisting of” and “mainly consisting of,” for example, “A includes a” covers the meanings of “A includes a and other” and “A only includes a.”

[0032] In this document, in order to make the description concise, not all possible combinations of various technical features in various embodiments or examples are described. Therefore, as long as there is no contradiction in the combination of these technical features, the various technical features in various embodiments or examples can be combined arbitrarily, and all possible combinations should be considered to be within the scope of this specification.

[0033] The present invention will be further described below in conjunction with specific embodiments. It should be understood that these embodiments are only used to illustrate the present invention and are not intended to limit the scope of the present invention. In addition, it should be understood that after reading the content taught by the present invention, those skilled in the art can make various changes or modifications to the present invention, and these equivalent forms fall within the scope limited by the appended claims of the application equally.

[0034] The following examples use conventional instruments and equipment in the art. The experimental methods in the following examples where specific conditions are not specified are usually carried out under conventional conditions or under conditions recommended by the manufacturer. The various raw materials used in the following examples are conventional commercial products unless otherwise specified, and their specifications are conventional specifications in the art. In the specification of the present invention and the following examples, unless otherwise specified, "%" means weight percentage, "part" means weight part, and ratio means weight ratio.

[0035] The present invention is further described in detail below in conjunction with specific embodiments, which are intended to explain the present invention rather than to limit it.

[0036] The present invention discloses a bulk passivated perovskite light absorbing layer, which is prepared by using a perovskite layer prefabricated solution, wherein the perovskite layer prefabricated solution comprises (FA 0.95 MA 0.05 ) 0.95 Cs 0.05 Pb(I 0.95 Br 0.05 )3 and mF-PEACl, preferably, the perovskite layer prefabricated solution (FA 0.95 MA 0.05 ) 0.95 Cs 0.05 Pb(I 0.95 Br 0.05 )3 and mF-PEACl has a molar ratio of 1.5:(0.2~0.6), preferably 1.5:(0.2~0.4), and optimally 1.5:0.3; the solvent of the perovskite layer prefabricated liquid is a mixture of N,N-dimethylformamide (DMF) and dimethyl sulfoxide (DMSO) in a volume ratio of 4:1.

[0037] By using mF-PEACl as a passivating agent and (FA 0.95 MA 0.05 ) 0.95 Cs 0.05 Pb(I 0.95 Br 0.05 )3 to form a bulk passivated perovskite layer. The organic cations in mF-PEACl can react with (FA 0.95 MA 0.05 ) 0.95 Cs 0.05 Pb(I 0.95 Br 0.05 )3 interacts with the uncoordinated lead ions or other defect sites in the perovskite to form a stable complex or composite, reducing the defect concentration inside the perovskite and achieving comprehensive and effective passivation.

[0038] See also Figure 1The present invention provides a perovskite solar cell, comprising a substrate 1 and a hole transport layer 2, a dielectric layer 3, the above-mentioned bulk passivated perovskite light absorbing layer 4, an electron transport layer 5 and a top electrode 6 sequentially arranged on the substrate 1; The substrate 1 is indium tin oxide conductive glass, and the thickness of the substrate is 200-400 nm, preferably 250-350 nm, and more preferably 290 nm, 300 nm, 310 nm or 320 nm; The hole transport layer 2 is one or more of MeO-2PACz, 2PACz, Me-4PACz and 4PACz, preferably MeO-2PACz; the thickness of the hole transport layer is 1 to 5 nm, preferably 1 to 3 nm, and more preferably 1 to 2 nm; The dielectric layer 3 is Al2O3 nanoparticles, the thickness of the dielectric layer is 30-60nm, preferably 30-60nm, and the particle size of the Al2O3 nanoparticles is 30nm or 100nm, preferably 30nm; The thickness of the bulk passivated perovskite light absorbing layer 4 is 300 to 700 nm, preferably 1 to 3 nm, and more preferably 1 to 2 nm; The electron transport layer 5 is one of TiO2, SnO2, fullerene and fullerene derivatives, preferably C 60 , the thickness of the electron transport layer is 10 to 100 nm, preferably 20 to 80 nm, more preferably 30 to 60 nm, and more preferably 40 to 50 nm; The top electrode 6 is made of gold, silver, copper, graphite or amorphous carbon, preferably gold. The thickness of the top electrode is 50 to 500 nm, preferably 100 to 400 nm, and more preferably 100 to 200 nm.

[0039] See also Figure 2 The present invention also provides a method for preparing the above-mentioned perovskite solar cell, comprising: S1: preparing a hole transport layer 2 on a substrate 1, specifically: The FTO glass substrate 1 is cleaned with acetone, isopropanol and deionized water in sequence, and then dried for later use; A hole transport solution with a concentration of 0.3-2 mg / mL) is spin-coated on a FTO glass substrate 1 at a rotation speed of 2000-6000 rpm, wherein the solute of the hole transport solution is one or more of MeO-2PACz, 2PACz, Me-4PACz and 4PACz, and the solvent is isopropanol, and annealing is performed at 80° C.-120° C. for 8-10 minutes to form a hole transport layer 2; S2: preparing a dielectric layer 3 on the hole transport layer 2, specifically: Spin coating an Al2O3 nanoparticle solution with a concentration of 0.8 to 1.2 mg / mL and a solvent of isopropanol on the hole transport layer 2 at a rotation speed of 2000 to 6000 rpm, and annealing at 80° C. to 120° C. for 8 to 10 minutes to form a dielectric layer 3; S3: Preparing a bulk passivation perovskite light absorbing layer 4 on the dielectric layer 3, specifically: Prepare (FA) at a concentration of 1.5 mol / L 0.95 MA 0.05 ) 0.95 Cs 0.05 Pb(I 0.95 Br 0.05 )3 perovskite precursor solution; the solvent is a mixture of DMF and DMSO in a volume ratio of 4:1; To (FA 0.95 MA 0.05 ) 0.95 Cs 0.05 Pb(I 0.95 Br 0.05 )3 Add mF-PEACl to the perovskite precursor solution to make the concentration of mF-PEACl 0.1-1 mg / mL to obtain a perovskite layer prefabricated solution; The perovskite layer prefabricated liquid is coated on the dielectric layer 3 at a rotation speed of 2000-6000 rpm, and chlorobenzene is quickly added as an anti-solvent 15 seconds before the end of the spin coating, and annealed at 80° C.-120° C. for 25-35 minutes to form a bulk passivated perovskite light absorbing layer 4; S4: preparing an electron transport layer 5 on the phase-passivated perovskite light-absorbing layer 4, specifically: On the bulk passivated perovskite light absorbing layer 4, an electron transport layer 5 is prepared by vacuum evaporation; S5: preparing a top electrode 6 on the electron transport layer 5 to complete the preparation of the perovskite solar cell, specifically: On the electron transport layer 5, a top electrode 6 is formed by vacuum evaporation.

[0040] Example 1 The FTO glass substrate was cleaned with acetone, isopropanol, and deionized water in sequence, and then dried for later use; A 0.6 mg / mL MeO-2PACz solution was spin-coated on the FTO glass substrate at 3000 rpm for 30 s and annealed at 100 °C for 10 min to form a hole transport layer; A 1 mg / mL Al2O3 nanoparticle solution was spin-coated on the hole transport layer at 5000 rpm for 30 s and annealed at 100°C for 10 min to form a dielectric layer. Prepare (FA) at a concentration of 1.5 mol / L according to the stoichiometric ratio 0.95 MA 0.05 ) 0.95 Cs 0.05 Pb(I 0.95 Br 0.05 )3 perovskite precursor solution, to (FA 0.95 MA 0.05 ) 0.95 Cs 0.05 Pb(I 0.95 Br 0.05 )3 Add mF-PEACl to the perovskite precursor solution to make the concentration of mF-PEACl 0.3 mg / mL to obtain a perovskite layer prefabricated solution; take 100 μL of the perovskite layer prefabricated solution and spin coat it on the dielectric layer at a speed of 2000 rpm for 10 seconds, then spin coat it at a speed of 5000 rpm for 40 seconds, and quickly add 200 μL of chlorobenzene as an anti-solvent 15 seconds before the end of spin coating, anneal on a hot stage at 100°C for 30 minutes to form a bulk passivated perovskite light-absorbing layer. Prepare the electron transport layer C on the bulk passivated perovskite light-absorbing layer by vacuum evaporation 60 , with a thickness of about 40nm, and finally, the top electrode gold is prepared by vacuum evaporation method with a thickness of about 100nm to obtain a perovskite solar cell.

[0041] Example 2 The FTO glass substrate was cleaned with acetone, isopropanol, and deionized water in sequence, and then dried for later use; A 0.6 mg / mL Me-4PACz solution was spin-coated on the FTO glass substrate at 3000 rpm for 30 s and annealed at 100 °C for 10 min to form a hole transport layer; A 1 mg / mL Al2O3 nanoparticle solution was spin-coated on the hole transport layer at 5000 rpm for 30 s and annealed at 100°C for 10 min to form a dielectric layer. Prepare (FA) at a concentration of 1.5 mol / L according to the stoichiometric ratio 0.95 MA 0.05 ) 0.95 Cs 0.05 Pb(I 0.95 Br 0.05 )3 perovskite precursor solution, to (FA 0.95 MA 0.05 ) 0.95 Cs 0.05 Pb(I 0.95 Br 0.05)3 Add mF-PEACl to the perovskite precursor solution to make the concentration of mF-PEACl 0.3mg / mL to obtain a perovskite layer prefabricated solution; take 100μL of the perovskite layer prefabricated solution and spin coat it on the dielectric layer at a speed of 2000rpm for 10s, then spin coat it at a speed of 5000rpm for 40s, quickly add 200μL of chlorobenzene as an anti-solvent 15s before the end of spin coating, anneal on a hot stage at 100℃ for 30min to form a bulk passivated perovskite light-absorbing layer. Prepare the electron transport layer SnO2 on the bulk passivated perovskite light-absorbing layer by vacuum evaporation method, with a thickness of about 40nm, and finally prepare the top electrode silver by vacuum evaporation method, with a thickness of about 100nm, to obtain a perovskite solar cell.

[0042] Example 3 The FTO glass substrate was cleaned with acetone, isopropanol, and deionized water in sequence, and then dried for later use; A 1 mg / mL 2PACz solution was spin-coated on the FTO glass substrate at 5000 rpm for 30 s and annealed at 100 °C for 10 min to form a hole transport layer; A 1 mg / mL Al2O3 nanoparticle solution was spin-coated on the hole transport layer at 5000 rpm for 30 s and annealed at 100°C for 10 min to form a dielectric layer. Prepare (FA) at a concentration of 1.5 mol / L according to the stoichiometric ratio 0.95 MA 0.05 ) 0.95 Cs 0.05 Pb(I 0.95 Br 0.05 )3 perovskite precursor solution, to (FA 0.95 MA 0.05 ) 0.95 Cs 0.05 Pb(I 0.95 Br 0.05 )3 Add mF-PEACl to the perovskite precursor solution to make the concentration of mF-PEACl 0.4mg / mL to obtain a perovskite layer prefabricated solution; take 100μL of the perovskite layer prefabricated solution and spin coat it on the dielectric layer at a speed of 2000rpm for 10s, then spin coat it at a speed of 5000rpm for 40s, quickly add 200μL of chlorobenzene as an anti-solvent 15s before the end of spin coating, anneal on a hot stage at 100℃ for 30min to form a bulk passivated perovskite light-absorbing layer. Prepare the electron transport layer TiO2 and SnO2 on the bulk passivated perovskite light-absorbing layer by vacuum evaporation method, with a thickness of about 40nm, and finally prepare the top electrode silver by vacuum evaporation method, with a thickness of about 100nm, to obtain a perovskite solar cell.

[0043] Example 4 The FTO glass substrate was cleaned with acetone, isopropanol, and deionized water in sequence, and then dried for later use; A 1 mg / mL 4PACz solution was spin-coated on the FTO glass substrate at 5000 rpm for 30 s and annealed at 80 °C for 12 min to form a hole transport layer; A 1 mg / mL Al2O3 nanoparticle solution was spin-coated on the hole transport layer at 3000 rpm for 50 s and annealed at 120°C for 8 min to form a dielectric layer. Prepare (FA) at a concentration of 1.5 mol / L according to the stoichiometric ratio 0.95 MA 0.05 ) 0.95 Cs 0.05 Pb(I 0.95 Br 0.05 )3 perovskite precursor solution, to (FA 0.95 MA 0.05 ) 0.95 Cs 0.05 Pb(I 0.95 Br 0.05 )3 Add mF-PEACl to the perovskite precursor solution to make the concentration of mF-PEACl 0.6mg / mL to obtain a perovskite layer prefabricated solution; take 100μL of the perovskite layer prefabricated solution and spin coat it on the dielectric layer at a speed of 3000rpm for 10s, then spin coat it at a speed of 6000rpm for 40s, quickly add 200μL of chlorobenzene as an anti-solvent 15s before the end of spin coating, and anneal on a hot stage at 100℃ for 30min to form a bulk passivated perovskite light-absorbing layer. Prepare the electron transport layer TiO2 on the bulk passivated perovskite light-absorbing layer by vacuum evaporation, and finally prepare the top electrode amorphous carbon by vacuum evaporation to obtain a perovskite solar cell.

[0044] Example 5 The FTO glass substrate was cleaned with acetone, isopropanol, and deionized water in sequence, and then dried for later use; A 1 mg / mL 2PACz solution was spin-coated on the FTO glass substrate at 4000 rpm for 30 s and annealed at 120 °C for 8 min to form a hole transport layer; A 0.3 mg / mL Al2O3 nanoparticle solution was spin-coated on the hole transport layer at 4000 rpm, the particle size of the Al2O3 nanoparticles was 30 nm, and the coating was performed for 40 s, followed by annealing at 120°C for 8 min to form a dielectric layer. Prepare (FA) at a concentration of 1.5 mol / L according to the stoichiometric ratio 0.95 MA 0.05 ) 0.95 Cs 0.05 Pb(I 0.95 Br0.05 )3 perovskite precursor solution, to (FA 0.95 MA 0.05 ) 0.95 Cs 0.05 Pb(I 0.95 Br 0.05 )3 Add mF-PEACl to the perovskite precursor solution to make the concentration of mF-PEACl 0.5mg / mL to obtain a perovskite layer prefabricated solution; take 100μL of the perovskite layer prefabricated solution and spin coat it on the dielectric layer at a speed of 2000rpm for 10s, then spin coat it at a speed of 6000rpm for 30s, quickly add 200μL of chlorobenzene as an anti-solvent 15s before the end of spin coating, anneal on a hot stage at 100℃ for 30min to form a bulk passivated perovskite light-absorbing layer. Prepare an electron transport layer SnO2 on the bulk passivated perovskite light-absorbing layer by vacuum evaporation with a thickness of about 40nm, and finally prepare a top electrode graphite by vacuum evaporation with a thickness of about 100nm to obtain a perovskite solar cell.

[0045] Example 6 The FTO glass substrate was cleaned with acetone, isopropanol, and deionized water in sequence, and then dried for later use; A 0.5 mg / mL 2PACz solution was spin-coated on the FTO glass substrate at 3000 rpm for 50 s and annealed at 90 °C for 9 min to form a hole transport layer. A 1 mg / mL Al2O3 nanoparticle solution was spin-coated on the hole transport layer at 5000 rpm for 30 s and annealed at 100°C for 10 min to form a dielectric layer. Prepare (FA) at a concentration of 1.5 mol / L according to the stoichiometric ratio 0.95 MA 0.05 ) 0.95 Cs 0.05 Pb(I 0.95 Br 0.05 )3 perovskite precursor solution, to (FA 0.95 MA 0.05 ) 0.95 Cs 0.05 Pb(I 0.95 Br 0.05)3 Add mF-PEACl to the perovskite precursor solution to make the concentration of mF-PEACl 0.7 mg / mL to obtain a perovskite layer prefabricated solution; take 100 μL of the perovskite layer prefabricated solution and spin coat it on the dielectric layer at a speed of 3000 rpm for 15 seconds, then spin coat it at a speed of 6000 rpm for 30 seconds, and quickly add 200 μL of chlorobenzene as an anti-solvent 15 seconds before the end of spin coating, and anneal on a hot stage at 100°C for 30 minutes to form a bulk passivated perovskite light-absorbing layer. Prepare the electron transport layer C on the bulk passivated perovskite light-absorbing layer by vacuum evaporation 60 Finally, the top electrode silver is prepared by vacuum evaporation to obtain a perovskite solar cell.

[0046] Example 7 The FTO glass substrate was cleaned with acetone, isopropanol, and deionized water in sequence, and then dried for later use; A mixed solution of 2 mg / mL Me-4PACz and 4PACz was spin-coated on a FTO glass substrate at 3500 rpm for 30 s and annealed at 100 °C for 10 min to form a hole transport layer; A 1 mg / mL Al2O3 nanoparticle solution was spin-coated on the hole transport layer at 5000 rpm for 30 s and annealed at 100°C for 10 min to form a dielectric layer. Prepare (FA) at a concentration of 1.5 mol / L according to the stoichiometric ratio 0.95 MA 0.05 ) 0.95 Cs 0.05 Pb(I 0.95 Br 0.05 )3 perovskite precursor solution, to (FA 0.95 MA 0.05 ) 0.95 Cs 0.05 Pb(I 0.95 Br 0.05 )3 Add mF-PEACl to the perovskite precursor solution to make the concentration of mF-PEACl 0.4 mg / mL to obtain a perovskite layer prefabricated solution; take 100 μL of the perovskite layer prefabricated solution and spin coat it on the dielectric layer at a speed of 2000 rpm for 10 seconds, then spin coat it at a speed of 5000 rpm for 40 seconds, and quickly add 200 μL of chlorobenzene as an anti-solvent 15 seconds before the end of spin coating, anneal on a hot stage at 100°C for 30 minutes to form a bulk passivated perovskite light-absorbing layer. Prepare the electron transport layer C on the bulk passivated perovskite light-absorbing layer by vacuum evaporation 60 Finally, the top electrode silver is prepared by vacuum evaporation to obtain a perovskite solar cell.

[0047] Example 8 The FTO glass substrate was cleaned with acetone, isopropanol, and deionized water in sequence, and then dried for later use; 1.5 mg / mL 2PACz and 4PACz solutions were spin-coated on FTO glass substrates at 5000 rpm for 30 s and annealed at 100 °C for 10 min to form a hole transport layer; A 1 mg / mL Al2O3 nanoparticle solution was spin-coated on the hole transport layer at 5000 rpm for 30 s and annealed at 100°C for 10 min to form a dielectric layer. Prepare (FA) at a concentration of 1.5 mol / L according to the stoichiometric ratio 0.95 MA 0.05 ) 0.95 Cs 0.05 Pb(I 0.95 Br 0.05 )3 perovskite precursor solution, to (FA 0.95 MA 0.05 ) 0.95 Cs 0.05 Pb(I 0.95 Br 0.05 )3 Add mF-PEACl to the perovskite precursor solution to make the concentration of mF-PEACl 0.4mg / mL to obtain a perovskite layer prefabricated solution; take 100μL of the perovskite layer prefabricated solution and spin coat it on the dielectric layer at a speed of 2000rpm for 10s, then spin coat it at a speed of 5000rpm for 40s, quickly add 200μL of chlorobenzene as an anti-solvent 15s before the end of spin coating, anneal on a hot stage at 100℃ for 30min to form a bulk passivated perovskite light-absorbing layer. Prepare the electron transport layer TiO2 and SnO2 on the bulk passivated perovskite light-absorbing layer by vacuum evaporation method, with a thickness of about 40nm, and finally prepare the top electrode silver by vacuum evaporation method, with a thickness of about 100nm, to obtain a perovskite solar cell.

[0048] Comparative Example 1 A 0.6 mg / mL MeO-2PACz solution was spin-coated on the FTO glass substrate at 3000 rpm for 30 seconds and then annealed at 100°C for 10 minutes to form a hole transport layer. A 1 mg / mL aluminum oxide nanoparticle solution was spin-coated on the hole transport layer at 5000 rpm for 30 seconds and then annealed at 100°C for 10 minutes to form a dielectric layer. 0.95 MA 0.05 ) 0.95 Cs 0.05 Pb(I 0.95 Br 0.05)3 Perovskite precursor solution, take 100μL of the precursor solution and apply it on the dielectric layer, spin coating for 10s at a speed of 2000rpm, spin coating for 40s at a speed of 5000rmp, quickly add 200μL of chlorobenzene as an anti-solvent 15s before the end of spin coating, and then anneal the perovskite film at 100℃ on a hot stage for 30min to form a perovskite light absorption layer, and prepare the electron transport layer C on the perovskite layer by vacuum evaporation. 60 , metal electrode gold is prepared by vacuum evaporation to obtain solar cells.

[0049] Comparative Example 2 A 0.6 mg / mL MeO-2PACz solution was spin-coated on the FTO glass substrate at 3000 rpm for 30 seconds and then annealed at 100°C for 10 minutes to form a hole transport layer. A 1 mg / mL aluminum oxide nanoparticle solution was spin-coated on the hole transport layer at 5000 rpm for 30 seconds and then annealed at 100°C for 10 minutes to form a dielectric layer. 0.95 MA 0.05 ) 0.95 Cs 0.05 Pb(I 0.95 Br 0.05 )3 Perovskite precursor solution, take 100 μL of the precursor solution and apply it on the dielectric layer, spin-coat for 10 seconds at a speed of 2000 rpm, spin-coat for 40 seconds at a speed of 5000 rpm, quickly add 200 μL of chlorobenzene as an anti-solvent 15 seconds before the end of spin coating, and then anneal the perovskite film at 100°C on a hot stage for 30 minutes to form a perovskite light-absorbing layer; spin-coat 0.5 mg / mL of a passivator solution on the perovskite layer, wherein the passivator in the passivator solution is mF-PEACl and the solvent is isopropanol, spin-coat for 30 seconds at a speed of 3000 rpm, and then anneal at 100°C for 10 minutes to form a passivation layer; prepare an electron transport layer C on the passivation layer by vacuum evaporation 60 , metal electrode gold is prepared by vacuum evaporation to obtain solar cells.

[0050] To further demonstrate the beneficial effects of the present invention, the perovskite solar cells prepared in Example 1 and the comparative example were subjected to performance tests, and the results are shown in the following table:

[0051] It can be seen that the open circuit voltage and fill factor of the perovskite solar cell prepared in Example 1 are higher than those of the perovskite solar cell in Comparative Example 1 which has not been subjected to bulk passivation treatment and the perovskite solar cell in Comparative Example 2 which has been subjected to surface passivation. This indicates that bulk passivation can effectively reduce defects in the perovskite film layer, thereby improving cell efficiency. At the same time, it can be seen that the fill factor, which is sensitive to carrier transport, is also improved, and mF-PEACl bulk passivation will not hinder carrier transport inside the perovskite.

[0052] In summary, the present invention provides a bulk passivated perovskite light absorbing layer, a solar cell and a preparation method thereof, using mF-PEACl as a passivating agent and (FA 0.95 MA 0.05 ) 0.95 Cs 0.05 Pb(I 0.95 Br 0.05 )3 to form a bulk passivated perovskite layer, so that the organic cations in mF-PEACl and (FA 0.95 MA 0.05 ) 0.95 Cs 0.05 Pb(I 0.95 Br 0.05 )3 interacts with the uncoordinated lead ions or other defect sites in the perovskite to form a stable complex or composite, reducing the defect concentration inside the perovskite and achieving comprehensive and effective passivation, thereby improving the photoelectric properties and stability of the perovskite material.

[0053] The above description is only a preferred embodiment of the present invention and is not intended to impose any limitation on the technical solution of the present invention. Those skilled in the art should understand that, without departing from the spirit and principles of the present invention, the technical solution can also be subjected to several simple modifications and substitutions, and these modifications and substitutions are also within the scope of protection covered by the claims.

Claims

1. A bulk passivated perovskite light absorbing layer, characterized in that: The perovskite layer prefabricated solution is used for preparation, wherein the perovskite layer prefabricated solution includes (FA 0.95 MA 0.05 ) 0.95 Cs 0.05 Pb(I 0.95 Br 0.05 )3 and mF-PEACl.

2. The bulk passivated perovskite light absorbing layer according to claim 1, characterized in that: The solvent of the perovskite layer prefabricated solution is a mixture of DMF and DMSO.

3. The bulk passivated perovskite light absorbing layer according to claim 2, characterized in that: The volume ratio of DMF to DMSO is 4:

1.

4. A perovskite solar cell, characterized in that: It comprises a substrate and a bulk passivated perovskite light absorbing layer as claimed in any one of claims 1 to 3; A hole transport layer, a dielectric layer, an electron transport layer and a top electrode are sequentially arranged on the substrate; The bulk passivation perovskite light absorbing layer is arranged between the dielectric layer and the electron transport layer.

5. The perovskite solar cell according to claim 4, characterized in that: The substrate is indium tin oxide conductive glass, and the thickness of the substrate is 200-400nm.

6. The perovskite solar cell according to claim 4, characterized in that: The hole transport layer is one or more of MeO-2PACz, 2PACz, Me-4PACz and 4PACz, and the thickness of the hole transport layer is 1 to 5 nm.

7. The perovskite solar cell according to claim 4, characterized in that: The dielectric layer is Al2O3 nanoparticles, and the thickness of the dielectric layer is 30-60nm.

8. The perovskite solar cell according to claim 4, characterized in that: The thickness of the bulk passivated perovskite light-absorbing layer is 300-700 nm; the electron transport layer is one of TiO2, SnO2, fullerene and fullerene derivatives, and the thickness of the electron transport layer is 10-100 nm.

9. The perovskite solar cell according to claim 4, characterized in that: The top electrode is one of gold, silver, copper, graphite and amorphous carbon, and the thickness of the top electrode is 50-500nm.

10. The method for preparing a perovskite solar cell according to any one of claims 4 to 9, characterized in that: include: preparing a hole transport layer on a substrate; preparing a dielectric layer on the hole transport layer; preparing a bulk passivated perovskite light absorbing layer on the dielectric layer; preparing an electron transport layer on the phase-passivated perovskite light-absorbing layer; A top electrode is prepared on the electron transport layer to complete the preparation of the perovskite solar cell.

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