Perovskite solar cell, preparation method and application thereof, and photovoltaic module

Abstract

The invention relates to a perovskite solar cell, a preparation method and application thereof, and a photovoltaic module. The preparation method of the perovskite solar cell comprises the following steps: preparing an electron transport layer on the surface of a first electrode, wherein the electron transport layer comprises oxygen atoms; arranging the modification solution on the surface, away from the first electrode, of the electron transport layer, and performing annealing treatment to form a modified layer; the modified solution comprises tetrabutylammonium chloride, and the concentration of the modified solution is 0.1 mg / mL to 1.5 mg / mL; and sequentially preparing a perovskite light absorption layer and a second electrode on the surface, far away from the electron transport layer, of the modified layer. According to the preparation method, the photoelectric conversion efficiency and the stability of the perovskite solar cell can be effectively improved.

Description

Technical Field

[0001] The present application relates to the field of photovoltaic technology, and in particular to a perovskite solar cell and a preparation method and application thereof, and a photovoltaic module. Background Art

[0002] With the rapid development of science and technology, modern society has an increasing demand for energy. Traditional fossil energy, as the main energy source, will cause serious environmental pollution during use. Solar cells have attracted widespread attention due to their green, efficient and clean characteristics. Perovskite solar cells (PSCs), as a new type of photovoltaic cell, have the advantages of adjustable bandgap, long carrier lifetime, and long diffusion distance, and are hailed as the next generation of the most promising solar cells. However, the photoelectric conversion efficiency and stability of traditional perovskite solar cells need to be further improved. Summary of the invention

[0003] Based on this, the present application provides a perovskite solar cell with high photoelectric conversion efficiency and good stability performance, as well as a preparation method and application thereof, and a photovoltaic module.

[0004] The technical solution of this application to solve the above technical problems is as follows.

[0005] The first aspect of the present application provides a method for preparing a perovskite solar cell, comprising the following steps:

[0006] Preparing an electron transport layer on the surface of the first electrode, wherein the electron transport layer includes oxygen atoms;

[0007] Placing a modified solution on the surface of the electron transport layer away from the first electrode, and performing annealing treatment to form a modified layer; the modified solution comprises tetrabutylammonium chloride, and the concentration of the modified solution is 0.1 mg / mL to 1.5 mg / mL;

[0008] A perovskite light absorbing layer and a second electrode are sequentially prepared on a surface of the modified layer away from the electron transport layer.

[0009] In some of the embodiments, in the method for preparing a perovskite solar cell, the electron transport layer includes at least one of an oxygen-containing C60 derivative and a metal oxide.

[0010] In some of the embodiments, in the method for preparing a perovskite solar cell, the oxygen-containing C60 derivative includes at least one of PCBM and ICBA; and / or

[0011] Metal oxides include TiO 2 SnO 2 、ZnO、ZrO 2 ,GZO,IZO,FTO,ITO,BaSnO 3, at least one of tin titanium oxide and zinc tin oxide.

[0012] In some of the embodiments, in the method for preparing a perovskite solar cell, the solvent of the modified solution includes at least one of an alcohol solvent and an ester solvent.

[0013] In some of the embodiments, in the method for preparing a perovskite solar cell, the alcohol solvent includes at least one of ethanol, isopropanol, ethylene glycol, glycerol and n-butanol; and / or

[0014] The ester solvent includes ethyl acetate.

[0015] In some of the embodiments, in the method for preparing a perovskite solar cell, the method of applying the modified solution on the surface of the electron transport layer includes spin coating at a rotation speed of 2000 rpm / s to 4000 rpm / s.

[0016] In some of the embodiments, in the method for preparing a perovskite solar cell, the annealing treatment is performed at a temperature of 80° C. to 120° C. and for a time of 2 min to 20 min.

[0017] In some of the embodiments, in the method for preparing a perovskite solar cell, the method further comprises the step of preparing a hole transport layer between the perovskite light absorbing layer and the second electrode.

[0018] A second aspect of the present application provides a perovskite solar cell, which is prepared using the above-mentioned preparation method.

[0019] The third aspect of the present application provides the use of the above-mentioned perovskite solar cell in the preparation of photovoltaic modules.

[0020] A fourth aspect of the present application provides a photovoltaic module, comprising the above-mentioned perovskite solar cell.

[0021] Compared with the prior art, the preparation method of the perovskite solar cell of the present application has the following beneficial effects:

[0022] The preparation method of the perovskite solar cell of the present application adopts a modified solution to set a specific type of modified layer between the metal oxide electron transport layer and the perovskite light absorbing layer, and controls the concentration of the modified solution, which can effectively avoid the problem that the cations of tetrabutylammonium chloride in the modified solution enter the A position in the perovskite crystal to form 2D perovskite, thereby reducing the photoelectric conversion efficiency; at the same time, the steric hindrance of the cations of tetrabutylammonium chloride in the modified solution is large, which can effectively destroy the interaction between the bottom of the perovskite light absorbing layer and the metal oxide electron transport layer, thereby inhibiting the tensile stress of the perovskite light absorbing layer; and the chloride ions in the tetrabutylammonium chloride can regulate the growth of the perovskite, making the perovskite film more dense and uniform; and the tetrabutylammonium chloride can passivate the ion defects in the bottom interface of the perovskite, and has little effect on the carrier migration; the combined effect of multiple aspects can effectively improve the photoelectric conversion efficiency and stability of the perovskite solar cell. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] In order to more clearly illustrate the specific implementation methods of the present application or the technical solutions in the prior art, the drawings required for use in the specific implementation methods or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some implementation methods of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0024] Figure 1 This is a comparison chart of the light stability test of Example 1 and Comparative Example 1;

[0025] Figure 2 This is a comparison chart of thermal stability tests of Example 1 and Comparative Example 1;

[0026] Figure 3 This is a comparison chart of thermal stability tests of Example 1 and Comparative Example 4;

[0027] Figure 4 This is a comparison chart of the thermal stability tests of Comparative Example 4 and Comparative Example 6. DETAILED DESCRIPTION

[0028] References to embodiments of the present invention will now be provided in detail, one or more examples of which are described below. Each example is provided as an explanation rather than a limitation of the present invention. In fact, it will be apparent to those skilled in the art that various modifications and variations may be made to the present invention without departing from the scope or spirit of the present invention. For example, a feature illustrated or described as part of one embodiment may be used in another embodiment to produce a further embodiment.

[0029] Therefore, it is intended that the present invention covers such modifications and variations that fall within the scope of the appended claims and their equivalents. Other objects, features and aspects of the present invention are disclosed in or are obvious from the following detailed description. Those of ordinary skill in the art will appreciate that this discussion is only a description of exemplary embodiments and is not intended to limit the broader aspects of the present invention.

[0030] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art of the present invention. The terms used in the specification of the present invention herein are only for the purpose of describing specific embodiments and are not intended to limit the present invention.

[0031] The term "comprises", "comprising" or any other variant thereof is intended to cover non-exclusive inclusion, so that the process, method, article or equipment including a series of elements includes not only those elements, but also includes other elements not explicitly listed, or also includes elements inherent to such process, method, article or equipment. In the absence of more restrictions, the elements defined by the sentence "comprising one..." do not exclude the presence of other identical elements in the process, method, article or equipment including the elements. The indefinite articles "a kind of" and "an" before the elements or components of the present invention are not restrictive to the quantity requirements (i.e., the number of occurrences) of the elements or components. Therefore, "a" or "a kind of" should be interpreted as including one or at least one, and the elements or components in the singular form also include the plural form, unless the number clearly refers only to the singular form. The meaning of "multiple" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

[0032] The weight of the relevant components mentioned in the description of the embodiments of the present invention may not only refer to the specific content of each component, but also indicate the weight ratio between the components. Therefore, as long as the content of the relevant components is proportionally enlarged or reduced according to the description of the embodiments of the present invention, it is within the scope disclosed in the description of the embodiments of the present invention. Specifically, the weight described in the description of the embodiments of the present invention may be a mass unit known in the chemical industry such as μg, mg, g, kg, etc.

[0033] Except as shown in the operating examples or otherwise indicated, all numbers used in the specification and claims to indicate the amount of ingredients, physicochemical properties, etc. are understood to be adjusted by the term "about" in all cases. For example, therefore, unless otherwise indicated, the numerical parameters listed in the above specification and the attached claims are approximate values, and those skilled in the art can use the teachings disclosed herein to seek to obtain the desired properties and appropriately change these approximate values. The use of numerical ranges expressed as endpoints includes all numbers within the range and any range within the range, for example, 1 to 5 includes 1, 1.1, 1.3, 1.5, 2, 2.75, 3, 3.80, 4 and 5, etc.

[0034] The study found that the factors affecting the photoelectric conversion efficiency and stability of perovskite solar cells include: there is an interaction between the O in the oxygen-containing electron transport layer and the perovskite layer, and the thermal expansion coefficients between the perovskite light-absorbing layer and the oxygen-containing electron transport layer are different. During the cooling process to room temperature after annealing, tensile stress will be generated between the perovskite light-absorbing layer and the electron transport layer. This tensile stress will cause lattice distortion of the perovskite, change the crystal microstructure, and then produce some defects, which will have a certain impact on the stability and performance of the battery.

[0035] An embodiment of the present application provides a method for preparing a perovskite solar cell, comprising the following steps:

[0036] Step S10: preparing an electron transport layer on the surface of the first electrode, wherein the electron transport layer includes oxygen atoms.

[0037] In some of the examples, in step S10, the electron transport layer includes at least one of an oxygen-containing C60 derivative and a metal oxide.

[0038] In some of the examples, in step S10, the oxygen-containing C60 derivative includes at least one of PCBM ([6,6]-phenyl-C61-butyric acid methyl ester) and ICBA.

[0039] In some examples, in step S10, the metal oxide includes TiO 2 SnO 2 、ZnO、ZrO 2 ,GZO,IZO,FTO,ITO,BaSnO 3 、TiSnO x (Tin Titanium Oxide) and SnZnO x (zinc tin oxide).

[0040] It is understood that the metal oxide used as the electron transport layer may also include but is not limited to indium oxide (In 2 O 3), niobium pentoxide (Nb 2 O 5 )wait.

[0041] Step S20: placing a modified solution on the surface of the electron transport layer away from the first electrode, and performing annealing treatment to form a modified layer; the modified solution includes tetrabutylammonium chloride, and the concentration of the modified solution is 0.1 mg / mL to 1.5 mg / mL.

[0042] Tetrabutylammonium chloride, chemical formula is C 16 H 36 ClN, the structural formula is as follows:

[0043]

[0044] It will be appreciated that the concentration of the modified solution includes, but is not limited to, 0.1 mg / mL, 0.2 mg / mL, 0.3 mg / mL, 0.4 mg / mL, 0.5 mg / mL, 0.6 mg / mL, 0.7 mg / mL, 0.8 mg / mL, 0.9 mg / mL, 1.0 mg / mL, 1.1 mg / mL, 1.2 mg / mL, 1.3 mg / mL, 1.4 mg / mL, and 1.5 mg / mL; in some examples, the concentration may be within the range formed by any two of these point values ​​as end values, the same below.

[0045] In some of the examples, in step S20, the concentration of the modified solution is 0.1 mg / mL to 1.0 mg / mL.

[0046] Optionally, the concentration of the modified solution is 0.5 mg / mL to 1.0 mg / mL.

[0047] Furthermore, the concentration of the modified solution is 0.5 mg / mL to 0.8 mg / mL.

[0048] By controlling the concentration of the modified solution, a better effect of blocking the interaction between the oxygen-containing electron transport layer and the perovskite can be achieved, thereby effectively improving the photoelectric conversion efficiency and stability of the perovskite solar cell; if the concentration of the modified solution is too high, ammonium cations will enter the A site in the perovskite crystal to form a 2D perovskite, but there is an energy level matching problem between the 2D perovskite and the oxygen-containing electron transport layer, that is, there is a large potential barrier between the valence band top of the 2D perovskite and the valence band top of the oxygen-containing electron transport layer, which in turn affects the extraction of carriers by the oxygen-containing electron transport layer; if the concentration of the modified solution is too low, the effect of blocking the interaction between the oxygen-containing electron transport layer and the perovskite is poor.

[0049] In some examples, in step S20, the solvent of the modified solution includes at least one of an alcohol solvent and an ester solvent.

[0050] In some of the examples, in step S20, the alcohol solvent includes at least one of ethanol, isopropanol, ethylene glycol, glycerol, and n-butanol.

[0051] In some examples, in step S20, the ester solvent includes ethyl acetate.

[0052] Preferably, the solvent of the modifying solution comprises isopropanol.

[0053] In some of the examples, in step S20, the method of applying the modified solution on the surface of the electron transport layer includes spin coating, and the rotation speed is 2000 rpm / s~4000 rpm / s.

[0054] It will be appreciated that the rotation speed includes but is not limited to 2000 rpm / s, 2200 rpm / s, 2500 rpm / s, 2800 rpm / s, 3000 rpm / s, 3200 rpm / s, 3500 rpm / s, 3800 rpm / s, and 4000 rpm / s.

[0055] In some of the examples, in step S20, the annealing treatment is performed at a temperature of 80°C to 120°C and for a time of 2 min to 20 min.

[0056] It can be understood that the annealing temperature includes but is not limited to 80°C, 90°C, 100°C, 110°C, and 120°C, and the time includes but is not limited to 2 min, 5 min, 8 min, 10 min, 12 min, 15 min, 18 min, and 20 min.

[0057] Step S30: sequentially preparing a perovskite light absorbing layer and a second electrode on a surface of the modified layer away from the electron transport layer.

[0058] The preparation method of the perovskite solar cell of the present application adopts a modified solution to set a specific type of modified layer between the metal oxide electron transport layer and the perovskite light absorbing layer, and controls the concentration of the modified solution, which can effectively avoid the problem that the cations of tetrabutylammonium chloride in the modified solution enter the A position in the perovskite crystal to form 2D perovskite, thereby reducing the photoelectric conversion efficiency; at the same time, the steric hindrance of the cations of tetrabutylammonium chloride in the modified solution is large, which can effectively destroy the interaction between the bottom of the perovskite light absorbing layer and the metal oxide electron transport layer, thereby inhibiting the tensile stress of the perovskite light absorbing layer; and the chloride ions in the tetrabutylammonium chloride can regulate the growth of the perovskite, making the perovskite film more dense and uniform; and the tetrabutylammonium chloride can passivate the ion defects in the bottom interface of the perovskite, and has little effect on the carrier migration; the combined effect of multiple aspects can effectively improve the photoelectric conversion efficiency and stability of the perovskite solar cell.

[0059] Perovskite solar cells passivated with tetrabutylammonium chloride (aperture area 0.08 cm 2 )The highest PCE is 23.13%.

[0060] Using polymers as the modification layer between the electron transport layer and the perovskite light absorbing layer has little effect on improving battery performance, which may be because the polymer affects the migration of carriers.

[0061] In some of the examples, in step S30, the preparation method of the perovskite light absorbing layer includes but is not limited to one or more of spin coating, blade coating, evaporation, printing, spraying, spray pyrolysis, and slit coating.

[0062] In some of the examples, in step S30, the preparation method of the second electrode includes but is not limited to one or more of spin coating, doctor blade coating, evaporation, printing, spray coating, spray pyrolysis and slit coating.

[0063] In some of the examples, the method for preparing a perovskite solar cell further includes the step of preparing a hole transport layer between the perovskite light absorbing layer and the second electrode.

[0064] It can be understood that in the method for preparing the perovskite solar cell provided in the present application, a buffer layer, an interface modification layer, etc. commonly used in the art can also be prepared.

[0065] An embodiment of the present application provides a perovskite solar cell, which is prepared using the above-mentioned method for preparing a perovskite solar cell.

[0066] The perovskite solar cell prepared by the above-mentioned preparation method of the perovskite solar cell has good electrical performance and cycle performance.

[0067] It can be understood that the perovskite solar cell provided in the present application includes a first electrode, an electron transport layer, a modified layer, a perovskite light absorbing layer and a second electrode which are stacked; the electron transport layer includes oxygen atoms, and the modified layer includes tetrabutylammonium chloride.

[0068] In some of these examples, the thickness of the electron transport layer in perovskite solar cells is 1 nm~100 μm.

[0069] It is understood that the thickness of the electron transport layer includes but is not limited to 1 nm, 10 nm, 100 nm, 200 nm, 300 nm, 500 nm, 800 nm, 1 μm, 10 μm, 20 μm, 50 μm, and 100 μm.

[0070] In some of these examples, the perovskite solar cell has a perovskite light-absorbing layer comprising ABX 3 .

[0071] Wherein, A includes at least one of nitrogen-containing monovalent cations and monovalent metal cations; further, the nitrogen-containing monovalent cations include but are not limited to at least one of amine monovalent cations, diamine monovalent cations and guanidine monovalent cations; further, the amine monovalent cations include but are not limited to at least one of methylamine ion, methylenediamine ion, dimethylamine ion, ethylamine ion, n-octylamine ion, butylamine ion, dodecane ion, propylamine ion, ethylenediamine ion, phenylethylamine ion, 1-pyreneamine ion, 1-pyreneamine ion, 1-pyreneethylamine ion and 2-(4-fluorophenyl)ethylamine ion, the diamine monovalent cations include but are not limited to at least one of formamidinium ion and acetamidine ion, and the guanidine monovalent cations include but are not limited to guanidine ion (GA + ), monovalent metal cations include but are not limited to Cs + and Rb + At least one of the above.

[0072] In some of these examples, perovskite solar cells include MA + (Methylamine ion), FA + (formamidinium ion), Cs + , Rb + DMA + (dimethylamine ion), PEA + (phenylethylamine ion) and BA + (butylamine ion), B includes lead ion (Pb 2+ )、Zn ion(Zn 2+ ), gallium ions (Ga 2+ ), calcium ions (Ca 2+ ), tin ions (Sn 2+ ) and copper ions (Cu 2+ ) at least one; X includes Cl - Br - ,I - 、F - and thiocyanate ion (SCN - ) at least one of the following.

[0073] In some of these examples, the thickness of the perovskite light-absorbing layer in perovskite solar cells is 10 nm~100 μm.

[0074] It can be understood that the thickness of the perovskite light absorbing layer includes but is not limited to 10 nm, 100 nm, 200 nm, 300 nm, 500 nm, 800 nm, 1 μm, 10 μm, 20 μm, 50 μm, and 100 μm.

[0075] In some of these examples, perovskite solar cells have a band gap of 0.9 eV to 3.0 eV in the perovskite absorber layer.

[0076] In some of these examples, in the perovskite solar cell, at least one of the first electrode and the second electrode is a transparent conductive electrode.

[0077] In some of the examples, in the perovskite solar cell, one of the first electrode and the second electrode is a transparent conductive electrode, and the other is one of a transparent conductive electrode, a graphene electrode, and a metal electrode.

[0078] It can be understood that in the perovskite solar cell, the first electrode and the second electrode may be both transparent conductive electrodes; the first electrode may be a transparent conductive electrode and the second electrode may be one of a graphene electrode and a metal electrode; the first electrode may be one of a graphene electrode and a metal electrode and the second electrode may be a transparent conductive electrode. Further, when one of the first electrode and the second electrode is a transparent conductive electrode and the other is one of a graphene electrode and a metal electrode, the transparent conductive electrode is a transparent conductive substrate.

[0079] In some of these examples, in the perovskite solar cell, the first electrode is a transparent conductive electrode.

[0080] In some of these examples, in the perovskite solar cell, the transparent conductive electrode includes at least one of indium tin oxide (ITO), indium zinc oxide (IZO), tungsten-doped indium oxide (IWO), and aluminum-doped zinc oxide (AZO).

[0081] In some of these examples, in the perovskite solar cell, the metal electrode includes at least one of silver (Ag) and copper (Cu).

[0082] Optionally, the metal electrode includes at least one of a silver electrode and a copper electrode.

[0083] In some of these examples, in perovskite solar cells, the thicknesses of the first electrode and the second electrode are independently 1 nm to 10 μm.

[0084] It can be understood that the thickness of the first electrode and the second electrode independently include but are not limited to 1 nm, 10 nm, 100 nm, 200 nm, 300 nm, 500 nm, 800 nm, 1 μm, and 10 μm.

[0085] In some of the examples, in the perovskite solar cell, the hole transport layer includes but is not limited to a single molecule self-assembled material. Further, the hole transport layer includes but is not limited to [2-(9H-carbazole-9-yl)ethyl]phosphonic acid (2PACz), [2-(3,6-dimethoxy-9H-carbazole-9-yl)ethyl]phosphonic acid (MeO-2PACz), [4-(3,6-dimethyl-9H-carbazole-9-yl)butyl]phosphonic acid (Me-4PACz), benzoic acid, 4-[bis(2,4 -dimethoxybiphenyl-4-yl)amino]-biphenyl-4-carboxylic acid [MC-43], Spiro-OMeTAD (2,2',7,7'-tetrakis[N,N-di(4-methoxyphenyl)amino]-9,9'-spirobifluorene), PTAA (polyethylene terephthalate), P3HT (polymer of 3-hexylthiophene), PEDOT:PSS, Spiro-TTB, F4-TCNQ, F6TCNNQ, TAPC, NiOx, CuSCN, CuAlO2, V2O5, CdS, CdSe.

[0086] In some of these examples, the thickness of the hole transport layer in perovskite solar cells is 1 nm~100 μm.

[0087] It is understood that the thickness of the hole transport layer includes but is not limited to 1 nm, 10 nm, 100 nm, 200 nm, 300 nm, 500 nm, 800 nm, 1 μm, 10 μm, 20 μm, 50 μm, and 100 μm.

[0088] It can be understood that the features of the perovskite solar cell provided in the present application and the method for preparing the perovskite solar cell provided above can be applicable to each other.

[0089] One embodiment of the present application provides an application of the above-mentioned perovskite solar cell in the preparation of a photovoltaic module. Another embodiment of the present application provides a photovoltaic module, including the above-mentioned perovskite solar cell.

[0090] It can be understood that photovoltaic modules can be used in photovoltaic power stations, such as ground power stations, rooftop power stations, water power stations, etc., and can also be used in equipment or devices that use solar energy to generate electricity, such as user solar power supplies, solar street lights, solar cars, solar buildings, etc. It can also be understood that the application scenarios of photovoltaic systems include but are not limited to this, that is, photovoltaic systems can be used in all fields that require solar energy to generate electricity. Taking the photovoltaic power generation system network as an example, the photovoltaic system may include a photovoltaic array, a junction box and an inverter. The photovoltaic array can be an array combination of multiple photovoltaic modules. For example, multiple photovoltaic modules can form multiple photovoltaic arrays. The photovoltaic array is connected to the junction box. The junction box can converge the current generated by the photovoltaic array. The converged current flows through the inverter and is converted into the alternating current required by the mains power grid, and then connected to the mains network to achieve solar power supply.

[0091] The photovoltaic module provided in the present application can be used in, but is not limited to, electrical devices such as vehicles, ships or aircraft.

[0092] The embodiments of the present application provide an electric device, which may be, but is not limited to, a mobile phone, a tablet, a laptop, an electric toy, an electric tool, a battery car, an electric car, a ship, a spacecraft, etc. Among them, the electric toy may include a fixed or mobile electric toy, such as a game console, an electric car toy, an electric ship toy, and an electric airplane toy, etc., and the spacecraft may include an airplane, a rocket, a space shuttle, and a spacecraft, etc.

[0093] The present application is further described in detail below in conjunction with specific implementation methods, but the implementation methods of the present application are not limited thereto.

[0094] Example 1

[0095] (1) Clean the ITO conductive glass, blow dry it and treat it with UV ozone;

[0096] (2) SnO 2 Solution (15%wt SnO 2 The solution was diluted with deionized water in a volume ratio of 1:5) and then spin-coated onto the ITO conductive glass at a speed of 3000 rpm for 30 s, and then annealed at 150 °C for 30 min to obtain an electron transport layer;

[0097] (3) Dissolve tetrabutylammonium chloride in isopropanol to obtain a modified solution with a concentration of 0.5 mg / mL, spin-coat 60 μL of the modified solution on the electron transport layer at a speed of 4000 rpm for 20 s, and then anneal on a hot plate at 100 °C for 5 min to obtain a modified layer;

[0098] (4) Weigh 1.2 g PbI 2, 25.35 mg CsI, 13.15 mg PbCl 2 Place it in a 3 mL solution, then add 1350 mL of DMF solvent and 150 mL of DMSO solvent (the volume ratio of DMF to DMSO is 9:1), then weigh a certain amount of 4F 2 M-BACl was added to a mixed solvent of DMF and DMSO, heated and stirred on a hot plate at 70°C for 8 h to obtain solution A. In addition, 108 mg of FAI, 10.8 mg of MACl, and 10.8 mg of MABr were weighed and placed in another 3 mL glass bottle. 1.8 mL of IPA was added and placed on a stirring plate and stirred at room temperature for 2 h to obtain solution B. 80 μL of PbI 2 The solution was dropped onto the modified layer and spin-coated at 1500 rpm for 30 s, then annealed on a 70° hot plate for 15 s. Then 100 μL of the mixed solution (FAI, MACl, MABr) was spin-coated on the PbI at 1500 rpm. 2 The film was then transferred to a hot plate at 150 °C for 15 min annealing to obtain a perovskite light-absorbing layer.

[0099] (5) Weigh 72.3 mg of Spiro-MeOTAD, then add 1 mL of CB, 28.8 ml of tBP, and 13.5 μL of LiTFSI. Place the mixture on a stirring table and stir for 2 h. Then let it stand and spin-coat the solution onto the perovskite light-absorbing layer for 30 s to obtain a hole transport layer.

[0100] (6) Use thermal evaporation to prepare the Ag electrode with a thickness of 150 nm to complete the battery preparation.

[0101] Example 2

[0102] The method is basically the same as Example 1, except that in step (3), the concentration of the modified solution is 0.8 mg / mL.

[0103] Example 3

[0104] The method is basically the same as Example 1, except that in step (3), the concentration of the modified solution is 1.0 mg / mL.

[0105] Example 4

[0106] The method is basically the same as Example 1, except that in step (3), the concentration of the modified solution is 1.5 mg / mL.

[0107] Example 5

[0108] The method is basically the same as Example 1, except that in step (3), the concentration of the modified solution is 0.1 mg / mL.

[0109] Example 6

[0110] The method is basically the same as Example 1, except that in step (3), the solvent of the modified solution is ethanol.

[0111] Example 7

[0112] The method is basically the same as Example 1, except that in step (3), the solvent of the modified solution is a mixed solvent of ethyl acetate, ethanol and isopropanol in a volume ratio of 50:50:900.

[0113] Comparative Example 1

[0114] The method is basically the same as Example 1, except that step (3) is omitted and the prepared battery has no modified layer.

[0115] Comparative Example 2

[0116] The method is basically the same as Example 1, except that in step (3), the tetrabutylammonium chloride in the modified solution is replaced with EDBECl of equal concentration. 2 (2,2'-(ethylenedioxy)bisethylamine hydrochloride).

[0117] Comparative Example 3

[0118] The method is basically the same as Example 1, except that in step (3), the concentration of the modified solution is 2.0 mg / mL.

[0119] Comparative Example 4

[0120] The method is basically the same as Example 1, except that step (2) is as follows: a C60 electron transport layer is prepared on the ITO conductive glass by evaporation, wherein the evaporation rate of C60 is 1 nm / min~5 nm / min, and the thickness of C60 is 20 nm.

[0121] Comparative Example 5

[0122] The method is basically the same as Example 1, except that in step (3), the tetrabutylammonium chloride in the modified solution is replaced with EDBECl of equal concentration. 2 (2,2'-(ethylenedioxy)bisethylamine hydrochloride).

[0123] The perovskite solar cells prepared in each embodiment and comparative example were subjected to performance tests of open circuit voltage, short circuit current density, fill factor and energy conversion efficiency. The IV curve was used for the test. The test conditions were: AM 1.5G standard solar spectrum, irradiance of 1000W / m 2 The experimental test results are shown in Table 1. PCE represents the energy conversion efficiency in %, Voc represents the open circuit voltage in V, and Jsc represents the short circuit current density in mA / cm 2 , FF stands for fill factor, the unit is %.

[0124] Table 1

[0125]

[0126] As can be seen from Table 1, compared with Comparative Example 1, the electrical properties of the batteries prepared in each embodiment are better. Among them, it can be seen from Examples 1 to 5 and Comparative Example 3 that on the basis of the modified solution including a specific tetrabutylammonium chloride, the concentration of the modified solution has a greater influence on the electrical properties of the final battery; among them, the modified concentration of Comparative Example 3 is too large, which acts as a non-radiative recombination center, causing the PCE of the battery to decrease. It can be seen from Example 1 and Comparative Example 2 that, on the basis of a specific concentration, the use of a specific type of modified solution can effectively improve the electrical properties of perovskite solar cells; among them, Comparative Example 2 replaces the modified layer material with an olefin material, which affects the conductivity of the battery, thereby causing a decrease in electrical performance.

[0127] Some embodiments and comparative examples were subjected to light stability test and thermal stability test, wherein:

[0128] Figure 1 This is a comparison chart of the light stability test of Example 1 and Comparative Example 1. The test conditions are one sunlight intensity, a nitrogen environment, a temperature of 20-25°C, and a relative air humidity of <10%. Figure 1 It can be seen that after more than 500 hours of testing, Example 1 can still maintain more than 80% of the initial PCE, while Comparative Example 1 can only maintain 56% of the initial PCE. This is because the Cl in tetrabutylammonium chloride - Pb in perovskite 2+ Interaction, inhibition of Pb 2+ During light exposure, it is reduced to Pb, which then induces perovskite degradation.

[0129] Figure 2 This is a comparison chart of thermal stability tests of Example 1 and Comparative Example 1. The test conditions are: in a nitrogen environment, the temperature is 85°C, and the relative air humidity is <10%. After more than 200 hours of testing, the device of Example 1 can still maintain 82% of the initial PCE, while Comparative Example 1 can only maintain 61% of the initial PCE.

[0130] Figure 3 This is a comparison chart of the thermal stability test of the devices in Example 1 and Comparative Example 4. The test conditions are as follows: in a nitrogen environment, the temperature is 85°C and the relative air humidity is <10%. After 240 hours of testing, Example 1 and Comparative Example 4 maintained 81% and 17% of the initial efficiency, respectively. This shows that under the action of the tetrabutylammonium chloride modified layer, the stress generated between the oxygen-containing electron transport layer and the perovskite is relieved, and the thermal stability of the device is improved. Since the C60 electron transport layer material of the Comparative Example 4 device does not contain O atoms, the tetrabutylammonium chloride modified layer does not have a similar effect on the device.

[0131] Comparative Example 6

[0132] The process is basically the same as Comparative Example 4, except that step (3) is omitted and the prepared battery has no modified layer.

[0133] Figure 4 This is a comparison chart of the thermal stability test of Comparative Example 4 and Comparative Example 6. The test conditions are: in a nitrogen environment, the temperature is 85°C, and the relative air humidity is <10%. After 168 hours of testing, the devices of Comparative Example 4 and Comparative Example 6 retain 34% and 31% of the initial efficiency, respectively. The thermal stability of the devices of Comparative Example 4 and Comparative Example 6 is poor. This may be due to the energy level mismatch caused by the application of C60 in formal perovskite solar cells, which causes more carriers to accumulate at the interface between C60 and perovskite, resulting in poor stability.

[0134] The technical features of the above-described embodiments may be arbitrarily combined. To make the description concise, not all possible combinations of the technical features in the above-described embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0135] The above-described embodiments only express several implementation methods of the present application, which is convenient for understanding the technical solution of the present application in detail, but it cannot be understood as limiting the scope of protection of the invention patent. It should be pointed out that for ordinary technicians in this field, without departing from the concept of the present application, several modifications and improvements can be made, which all belong to the scope of protection of the present application. It should be understood that the technical solutions obtained by those skilled in the art through logical analysis, reasoning or limited experiments on the basis of the technical solutions provided in the present application are all within the scope of protection of the claims attached to the present application. Therefore, the scope of protection of the patent of this application shall be based on the contents of the attached claims, and the description and drawings can be used to explain the contents of the claims.

Claims

1. A method for preparing a perovskite solar cell, characterized in that: The following steps are involved: Preparing an electron transport layer on the surface of the first electrode, wherein the electron transport layer includes oxygen atoms; placing a modified solution on the surface of the electron transport layer away from the first electrode, and performing annealing treatment to form a modified layer; The modified solution includes tetrabutylammonium chloride, and the concentration of the modified solution is 0.1 mg / mL to 1.5 mg / mL; A perovskite light absorbing layer and a second electrode are sequentially prepared on a surface of the modified layer away from the electron transport layer.

2. The preparation method according to claim 1, characterized in that The electron transport layer includes at least one of an oxygen-containing C60 derivative and a metal oxide.

3. The preparation method according to claim 2, characterized in that: The oxygen-containing C60 derivative comprises at least one of PCBM and ICBA; and / or The metal oxide includes at least one of TiO2, SnO2, ZnO, ZrO2, GZO, IZO, FTO, ITO, BaSnO3, tin-titanium oxide and zinc-tin oxide.

4. The preparation method according to claim 1, characterized in that: The solvent of the modified solution includes at least one of an alcohol solvent and an ester solvent.

5. The preparation method according to claim 4, characterized in that: The alcohol solvent comprises at least one of ethanol, isopropanol, ethylene glycol, glycerol and n-butanol; and / or The ester solvent includes ethyl acetate.

6. The preparation method according to any one of claims 1 to 5, characterized in that: The modified solution is disposed on the surface of the electron transport layer by spin coating at a rotation speed of 2000 rpm / s to 4000 rpm / s.

7. The preparation method according to any one of claims 1 to 5, characterized in that The annealing treatment is performed at a temperature of 80°C to 120°C and for a time of 2 min to 20 min.

8. The preparation method according to any one of claims 1 to 5, characterized in that: The preparation method also includes the step of preparing a hole transport layer between the perovskite light absorbing layer and the second electrode.

9. A perovskite solar cell, characterized in that: The method is prepared according to any one of claims 1 to 8.

10. Use of the perovskite solar cell according to claim 9 in preparing a photovoltaic module.

11. A photovoltaic module, characterized in that: Comprising the perovskite solar cell as claimed in claim 9.

Images