Trans-perovskite solar cell and preparation method thereof

Abstract

The invention belongs to the photovoltaic field, and particularly relates to a trans-perovskite solar cell and a preparation method thereof. The trans-perovskite solar cell sequentially comprises a hole transport layer, a perovskite light absorption layer, a passivation layer and an electron transport layer in the thickness direction, the passivation layer is selected from one or more of tin oxide, aluminum oxide, silicon nitride and silicon carbide, and the thickness of the passivation layer is 0.15-0.45 nm. The passivation layer prepared by the invention can modify a perovskite light absorption layer and a C60 contact interface, thereby improving the efficiency and stability of the trans-perovskite solar cell comprising the passivation layer.

Description

Technical Field

[0001] The present invention belongs to the field of photovoltaics, and in particular relates to an inverse perovskite solar cell and a preparation method thereof. Background Art

[0002] Organic-inorganic hybrid perovskite materials have the advantages of high absorption coefficient, adjustable bandgap, long carrier diffusion length, high defect tolerance, simple preparation process, and low material and preparation costs. They are considered to be the new materials closest to commercialization in the photovoltaic market in recent years. After only more than a decade of research, single-junction perovskite solar cells have achieved a high photoelectric conversion efficiency, surpassing the currently commercialized cadmium telluride and copper indium gallium selenide cells, and are very close to the mainstream crystalline silicon (26.7%) solar cells in the market; at the same time, stacked perovskite solar cells have gradually become a hot topic in the world's photovoltaic research field in recent years because of their outstanding advantages such as high efficiency, low cost, and simple preparation process. They are considered to be one of the technologies that are expected to achieve large-scale terrestrial photovoltaic applications.

[0003] In the process of development of perovskite solar cells, they can also be divided into formal perovskite solar cells and inverted perovskite solar cells. Formal perovskite solar cells have a device structure in which an electron transport layer is first prepared on a substrate, and then a perovskite light absorption layer and a hole transport layer are prepared. Inverted perovskite solar cells have a device structure in which a hole transport layer is first prepared on a substrate, and then a perovskite light absorption layer and an electron transport layer are prepared. At present, the main electron transport layer materials used in formal perovskite solar cells are tin oxide, and the hole transport layer materials are Spiro-OMeTAD. Due to the high light absorption coefficient and poor photothermal stability of Spiro-OMeTAD, the formal structured stacked cells still rely on the development of new hole transport layers. The performance of inverse perovskite solar cells has developed rapidly in recent years, and its efficiency has exceeded that of formal cells. The commonly used hole transport layer materials for inverse perovskite solar cells are SAM materials, and the electron transport layer materials are C60 materials. The high contact defects between the perovskite light absorption layer and C60 in inverse perovskite solar cells cause significant efficiency losses; at the same time, the mechanical adhesion between the perovskite light absorption layer and C60 is poor, and the easy delamination of C60 seriously damages the stability of the battery.

[0004] At present, there are two main methods for treating the contact interface between the perovskite light absorption layer and C60: (1) introducing metal fluoride as a barrier material between the perovskite light absorption layer and C60; (2) using nitrogen-containing salts for surface passivation. Nitrogen-containing salts mainly include piperazine, amines, and diamines. In the first treatment method, due to the poor thermal stability of metal fluoride itself, LiF is used as the interface layer, and Li ions can migrate into the perovskite body, seriously affecting the performance of the device; MgF2 is used as the interface layer and can react at around 100°C, so metal fluoride cannot significantly improve the stability. In the second treatment method, the surface two-dimensional thin layer or polarization layer formed by nitrogen-containing salt passivation will migrate rapidly under photothermal conditions and eventually diffuse into the bulk phase of the perovskite, and can no longer play a passivation role, and the device efficiency will be significantly reduced; and this type of material fails to fundamentally change the contact interface between the perovskite light absorption layer and C60, and the delamination phenomenon of C60 is still significant.

[0005] Therefore, it is urgent to develop a passivation layer to modify the contact interface between the perovskite light absorption layer and C60, so as to improve the efficiency and stability of inverse perovskite solar cells. Summary of the invention

[0006] In order to solve the problems existing in the prior art, the present invention provides an inverted perovskite solar cell. The inverted perovskite solar cell of the present invention comprises a hole transport layer, a perovskite light absorption layer, a passivation layer and an electron transport layer in the thickness direction, the passivation layer is selected from one or more of tin oxide, aluminum oxide, silicon nitride and silicon carbide, the thickness of the passivation layer is 0.15-0.45nm, and the electron transport layer is C60. The passivation layer of the present invention can improve the efficiency and stability of the inverted perovskite solar cell.

[0007] Specifically, the present invention provides an inverted perovskite solar cell, which includes a hole transport layer, a perovskite light absorption layer, a passivation layer and an electron transport layer in sequence from the thickness direction, the passivation layer is selected from one or more of tin oxide, aluminum oxide, silicon nitride and silicon carbide, and the thickness of the passivation layer is 0.15-0.45nm.

[0008] In one or more embodiments, the electron transport layer is C60.

[0009] In one or more embodiments, the perovskite light absorption layer includes a perovskite structure material, the chemical formula of the perovskite structure material is ABX3, A is a monovalent cation, including but not limited to one or more of cesium ions, rubidium ions, methylamine ions and formamidine ions; B is a divalent cation, including but not limited to one or more of lead ions, copper ions, zinc ions, gallium ions, tin ions and calcium ions; X is a monovalent anion, including but not limited to one or more of iodide ions, bromide ions, chloride ions, fluoride ions, thiocyanate ions, tetrafluoroborate ions and hexafluorophosphate ions.

[0010] In one or more embodiments, the hole transport layer has a thickness of 1 to 30 nm.

[0011] In one or more embodiments, the perovskite light absorbing layer has a thickness of 300-3000 nm.

[0012] In one or more embodiments, the electron transport layer has a thickness of 2-30 nm.

[0013] The present invention provides a method for preparing the inverse perovskite solar cell of the present invention, the method comprising the following steps:

[0014] (1) depositing the perovskite light absorption layer on the surface of the hole transport layer;

[0015] (2) depositing the passivation layer on the surface of the perovskite light absorbing layer;

[0016] (3) Depositing the electron transport layer on the surface of the passivation layer to obtain an inverse perovskite solar cell.

[0017] In one or more embodiments, in step (1), the raw material of the perovskite structure material and the solvent are mixed to obtain a perovskite precursor solution, and then the perovskite precursor solution is coated on the surface of the hole transport layer, and then annealed to obtain the perovskite light absorbing layer.

[0018] In one or more embodiments, in step (1), in the perovskite precursor solution, the solvent is selected from one or more of ethanol, isopropanol, methanol, butanol, pentanol, N,N-dimethylformamide, dimethyl sulfoxide, 1,3-dimethyl-3,4,5,6-tetrahydro-2-pyrimidinone, acetonitrile, diphenyl sulfoxide and dimethoxyethanol.

[0019] In one or more embodiments, in step (1), the concentration of the theoretically generated perovskite structured substance in the perovskite precursor solution is 0.1-2.4 mol / L.

[0020] In one or more embodiments, in step (1), the coating method of the perovskite precursor solution is spin coating, blade coating, spray pyrolysis, inkjet printing or slit coating.

[0021] In one or more embodiments, in step (2), the tin oxide is deposited by atomic layer deposition, reactive ion sputtering or chemical vapor deposition.

[0022] In one or more embodiments, in step (2), the aluminum oxide is deposited by atomic layer deposition.

[0023] In one or more embodiments, in step (2), the deposition method of nitride and carbide is atomic layer deposition or chemical vapor deposition.

[0024] In one or more embodiments, in step (3), the electron transport layer is deposited by blade coating, slit coating or thermal evaporation. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 (a) is a schematic diagram of the structure of an inverted perovskite solar cell prepared in Example 1 of the present invention.

[0026] Figure 1 (b) is a schematic structural diagram of the inverted perovskite solar cell prepared in Comparative Example 1 of the present invention. DETAILED DESCRIPTION

[0027] 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.

[0028] 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.

[0029] Herein, “comprising”, “including”, “containing” and similar terms encompass the meanings of “consisting essentially of” and “consisting of”. For example, when “A comprises B and C” is disclosed herein, “A consists essentially of B and C” and “A consists of B and C” should be deemed to be disclosed herein.

[0030] In this article, all features such as values, quantities, contents and concentrations defined in the form of numerical ranges or percentage ranges are only for brevity and convenience. 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, percentage refers to mass percentage and ratio refers to mass ratio.

[0032] Herein, when describing embodiments or examples, it should be understood that they are not used to limit the present invention to these embodiments or examples. On the contrary, all substitutes, improvements and equivalents of the methods and materials described in the present invention can be included in the scope limited by the claims.

[0033] 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.

[0034] The present invention provides an inverted perovskite solar cell, which includes a hole transport layer, a perovskite light absorption layer, a passivation layer and an electron transport layer in sequence from the thickness direction, the passivation layer can be one or more selected from tin oxide, aluminum oxide, silicon nitride and silicon carbide, and the electron transport layer can be C60. The use of the passivation layer material of the present invention can change the phenomenon of direct contact between perovskite and C60, realize the isolation of the interface between the perovskite light absorption layer and C60, reduce the contact defect between the perovskite light absorption layer and C60, and improve the efficiency of the inverted perovskite solar cell; and the passivation layer and C60 have good adhesion, alleviate the delamination phenomenon, and improve the stability of the inverted perovskite solar cell; the ultra-thin passivation layer will not affect the transmission of carriers, but is sufficient to change the state of the surface of the perovskite light absorption layer, and the passivation layer will not react with the halogen, ammonium salt, etc. in the perovskite to diffuse into the bulk phase.

[0035] In the present invention, silicon nitride refers to a compound containing nitrogen and silicon, and the molar ratio of silicon to nitrogen in silicon nitride can be 3:4. In the present invention, silicon carbide refers to a compound containing carbon and silicon, and the molar ratio of silicon to carbon in silicon carbide can be 1:1.

[0036] In the present invention, the thickness of the passivation layer can be 0.15-0.45 nm, such as 0.15 mm, 0.20 mm, 0.25 mm, 0.30 mm, 0.35 mm, 0.40 mm, 0.45 mm. In the present invention, controlling the thickness of the passivation layer within the above range is beneficial to improving the photoelectric performance of the perovskite solar cell.

[0037] In the present invention, the hole transport layer can be an inorganic transport material and / or an organic p-type semiconductor material. In the present invention, the inorganic transport material can be one or more selected from nickel oxide (NiO), cuprous oxide (Cu2O), molybdenum oxide (MoO3), copper iodide (CuI) and redox graphene. In the present invention, the organic p-type semiconductor material can be selected from poly [bis (4-phenyl) (2,4,6-trimethylphenyl) amine] (PTAA, poly (triaryl amine)), 2,2',7,7'-tetrakis [N,N-di (4-methoxyphenyl) amino] -9,9'-spirobifluorene (Spiro-OMeTAD), poly 3,4-ethylenedioxythiophene: polystyrene sulfonate (PEDOT:PSS), poly [bis (4-phenyl) (4-butylphenyl) amine] (Ploy-TPD), [2- (9H-carbazole-9-yl) ethyl] phosphonic acid and [2- (3,6-dimethoxy-9H-carbazole-9-yl) ethyl] phosphonic acid (MeO-2PACz) One or more. In the present invention, the thickness of the hole transport layer can be 1-30nm, for example, 1mm, 5mm, 10mm, 15mm, 20mm, 25mm, 30mm.

[0038] In the present invention, the perovskite light absorption layer includes a perovskite structure material. In the present invention, the chemical formula of the perovskite structure material is ABX3, and A can be a monovalent cation, including but not limited to a cesium ion (Cs + ), rubidium ions (Rb + ), methylamine ion (CH3NH3 + , M.A. + ) and formamidinium ion (CH(NH2)2 + , F.A. + ) or more; B may be a divalent cation, including but not limited to lead ions (Pb 2+ ), copper ions (Cu 2+ ), zinc ion (Zn 2+ ), gallium ions (Ga 2+ ), tin ions (Sn 2+ ) and calcium ions (Ca 2+ ) in one or more; X may be a monovalent anion, including but not limited to iodide ion (I - ), bromide ion (Br - ), chloride ion (Cl - ), fluoride ion (F - ), thiocyanate ion (SCN - ), tetrafluoroborate ion (BF4 - ) and hexafluorophosphate ion (PF6 - )

[0039] In the present invention, the thickness of the perovskite light absorbing layer may be 300-3000 nm, for example, 300 mm, 500 mm, 1000 mm, 1500 mm, 2000 mm, 2500 mm, 3000 mm.

[0040] In the present invention, the thickness of the electron transport layer can be 2-30 nm, for example, 2 mm, 4 mm, 6 mm, 8 mm, 10 mm, 15 mm, 20 mm, 25 mm, and 30 mm.

[0041] The present invention provides a method for preparing an inverse perovskite solar cell of the present invention, the method comprising the following steps:

[0042] (1) depositing a perovskite light absorption layer on the surface of the hole transport layer;

[0043] (2) depositing a passivation layer on the surface of the perovskite light absorbing layer;

[0044] (3) Depositing an electron transport layer on the surface of the passivation layer to obtain an inverse perovskite solar cell.

[0045] In step (1), the raw material of the perovskite structure material and the solvent may be mixed to obtain a perovskite precursor solution, and then the perovskite precursor solution is coated on the surface of the hole transport layer, followed by annealing to obtain the perovskite light absorbing layer.

[0046] In step (1), in the perovskite precursor solution, the solvent can be one or more selected from ethanol, isopropanol, methanol, butanol, pentanol, N,N-dimethylformamide (DMF), dimethyl sulfoxide (DMSO), 1,3-dimethyl-3,4,5,6-tetrahydro-2-pyrimidone (DMPU), acetonitrile (ACN), diphenyl sulfoxide (DPSO) and dimethoxyethanol.

[0047] In step (1), the concentration of the theoretically generated perovskite structured substance in the perovskite precursor solution can be 0.1-2.4 mol / L, for example, 0.5 mol / L, 1.0 mol / L, 1.5 mol / L, 2.0 mol / L, 2.4 mol / L.

[0048] In step (1), the coating method of the perovskite precursor solution can be spin coating, blade coating, spray pyrolysis, inkjet printing or slit coating.

[0049] In step (2), the deposition method of tin oxide can be atomic layer deposition (ALD), reactive ion sputtering (RPD) or chemical vapor deposition (CVD).

[0050] In step (2), the aluminum oxide may be deposited by atomic layer deposition.

[0051] In step (2), the deposition method of nitride and carbide can be atomic layer deposition or chemical vapor deposition.

[0052] In step (3), the electron transport layer can be deposited by blade coating, slit coating or thermal evaporation.

[0053] In the present invention, the inverted perovskite solar cell may include an inverted single-junction perovskite solar cell or an inverted tandem perovskite solar cell.

[0054] In the present invention, the inverted single junction perovskite solar cell may further include a transparent conductive substrate and a back electrode. In some embodiments, the inverted single junction perovskite solar cell may include a transparent conductive substrate, a hole transport layer, a perovskite film, a passivation layer, an electron transport layer and a back electrode in sequence.

[0055] In the present invention, the transparent conductive substrate can be one or more of indium tin oxide (ITO), indium zinc oxide (IZO), cerium-doped indium oxide (ICO), tungsten-doped indium oxide (IWO), aluminum-doped zinc oxide (AZO), barium zirconate (BZO), fluorine-doped tin oxide (FTO) and indium oxide (IO).

[0056] In the present invention, the back electrode may be one or more selected from the group consisting of gold, palladium, silver, titanium, chromium, nickel, aluminum, copper, indium tin oxide (ITO) and indium zinc oxide (IZO).

[0057] In the present invention, the inverted stacked perovskite solar cell may also include a crystalline silicon-perovskite stacked cell, a perovskite-perovskite stacked cell, a perovskite-copper indium gallium selenide stacked cell, a perovskite-gallium arsenide stacked cell, an organic-perovskite stacked cell, a flexible perovskite cell, and a flexible stacked cell containing perovskite. In the present invention, the inverted stacked perovskite solar cell may also include a bottom electrode, a bottom cell, a tunneling layer, and a top electrode. In some embodiments, the inverted stacked perovskite solar cell may include a bottom electrode, a bottom cell, a tunneling layer, a hole transport layer, a perovskite film, a passivation layer, an electron transport layer, and a top electrode in sequence.

[0058] In the present invention, the bottom electrode may include a transparent conductive layer; preferably, the bottom electrode may also include a gate line electrode.

[0059] In the present invention, the transparent conductive layer can be selected from one or more of indium tin oxide (ITO), indium zinc oxide (IZO), cerium-doped indium oxide (ICO), tungsten-doped indium oxide (IWO), aluminum-doped zinc oxide (AZO), barium zirconate (BZO), fluorine-doped tin oxide (FTO) and indium oxide (IO).

[0060] In the present invention, the gate line electrode may be one or more selected from silver, copper, aluminum or alloys containing such metal elements.

[0061] In the present invention, the bottom cell may be a crystalline silicon bottom cell, a perovskite bottom cell, a copper indium gallium selenide bottom cell, a gallium arsenide bottom cell or an organic bottom cell.

[0062] In the present invention, the tunneling layer can be one or more of indium tin oxide (ITO), indium zinc oxide (IZO), cerium-doped indium oxide (ICO), tungsten-doped indium oxide (IWO), aluminum-doped zinc oxide (AZO), barium zirconate (BZO), fluorine-doped tin oxide (FTO) and indium oxide (IO).

[0063] In the present invention, the top electrode may include a transparent conductive layer; preferably, the top electrode may also include a gate line electrode; more preferably, the top electrode may also include an anti-reflection layer.

[0064] In some embodiments, preparing an inverse perovskite solar cell may include the following steps:

[0065] (1') depositing a hole transport layer on the surface of a transparent conductive substrate;

[0066] (1) depositing a perovskite light absorption layer on the surface of the hole transport layer;

[0067] (2) depositing a passivation layer on the surface of the perovskite light absorbing layer;

[0068] (3) depositing an electron transport layer on the surface of the passivation layer;

[0069] (3') depositing a back electrode on the surface of the electron transport layer to obtain an inverted single-junction perovskite solar cell. In some embodiments, the preparation of an inverted perovskite solar cell may include the following steps:

[0070] (1”) depositing a bottom electrode and a tunneling layer on both sides of the bottom battery respectively; depositing a hole transport layer on the surface of the tunneling layer;

[0071] (1) depositing a perovskite light absorption layer on the surface of the hole transport layer;

[0072] (2) depositing a passivation layer on the surface of the perovskite light absorbing layer;

[0073] (3) depositing an electron transport layer on the surface of the passivation layer;

[0074] (3”) A top electrode is deposited on the surface of the electron transport layer to obtain an inverted stacked perovskite solar cell.

[0075] Compared with the prior art, the present invention has the following beneficial effects:

[0076] (1) The present invention achieves the isolation of the interface between the perovskite film and C60, reduces the contact defects between the perovskite and C60, and improves the efficiency of the device;

[0077] (2) The present invention changes the phenomenon of direct contact between the perovskite film and C60, and the passivation layer has good adhesion to C60, which alleviates the delamination phenomenon and improves the stability of the device;

[0078] (3) The ultra-thin passivation layer will not affect the transport of carriers, but is sufficient to change the state of the perovskite surface, and the layer will not react with the halogens, ammonium salts, etc. in the perovskite to diffuse into the bulk phase.

[0079] The present invention will be described below in the form of specific examples. It should be understood that these examples are merely illustrative and are not intended to limit the scope of the present invention. The methods, reagents and materials used in the examples are, unless otherwise stated, conventional methods, reagents and materials in the art. The raw material compounds in the examples can all be purchased through commercial routes.

[0080] Example 1

[0081] Preparation of this example Figure 1 The inverted perovskite solar cell shown in (a) has the following specific preparation process:

[0082] 1. Preparation of bottom cell: Using plasma enhanced chemical vapor deposition (PECVD) process, intrinsic amorphous silicon layers (a-Si(i)) are deposited on both sides of the intrinsic silicon layer (c-Si(n)) at 200°C to obtain a passivation layer, and then n-type microcrystalline silicon layers and p-type microcrystalline silicon layers are deposited on both sides of the passivation layer to obtain an electron transport layer (nc-Si(p)) and a hole transport layer (nc-Si(p)), respectively, to obtain a bottom cell. The thickness of the bottom cell is 300μm.

[0083] 2. Preparation of back electrode and tunneling layer: ITO is deposited on the surface of p-type microcrystalline silicon layer by physical vapor deposition to obtain a transparent electrode layer with a thickness of 80nm, silver is printed on the surface of transparent electrode layer by printing method to obtain metal grid lines with a height of 20μm and a width of 30μm, and the transparent electrode layer and metal grid lines constitute the back electrode; ITO is deposited on the surface of n-type microcrystalline silicon layer by sputtering method to obtain a tunneling layer with a thickness of 20nm;

[0084] 3. Preparation of hole transport layer: [2-(3,6-dimethoxy-9H-carbazole-9-yl)ethyl]phosphonic acid (MeO-2PACz) was dissolved in ethanol to prepare a MeO-2PACz solution with a concentration of 1 mmol / mL. 130 μL of MeO-2PACz solution was added dropwise to the surface of the tunneling layer ITO, and then spin-coated at a speed of 4000 rpm for 15 seconds. After the spin coating, it was transferred to a hot plate at 100°C for annealing for 10 minutes, and then removed to obtain a hole transport layer with a thickness of 2 nm.

[0085] 4. Preparation of perovskite light absorption layer: 88.3 mg of cesium iodide (CsI), 233.9 mg of iodomethane (FAI), 187.2 mg of lead bromide (PbBr2), and 548.6 mg of lead iodide (PbI2) were dissolved in a mixed solvent of 800 μL DMF and 200 μL DMSO, and filtered using a 250 μm oily filter to obtain a perovskite precursor solution. The perovskite precursor solution contained 1.7 mol / L of theoretically generated FAI. 0.8 Cs 0.2 Pb(I 0.8 Br 0.2 )3; Prepare the perovskite light absorbing layer by scraping method; the specific operation is as follows: take 10μL perovskite precursor droplet on the scraper head, the scraper moves at a speed of 20mm / s, the scraper height is 100μm, and after scraping, use N2 air knife to blow, the blowing pressure is 0.4MPaMpa, the moving speed is 5mm / s, and after blowing, the perovskite film is annealed on a heating plate at 100°C for 10min to obtain a perovskite light absorbing layer, and the thickness of the perovskite light absorbing layer is 1500nm;

[0086] 5. Preparation of passivation layer: ALD is used to deposit aluminum oxide on the surface of the perovskite light absorption layer to obtain a passivation layer with a thickness of 0.15 nm. During the preparation process, the carrier gas is N2 with an N2 flow rate of 300 sccm, the aluminum source is trimethylaluminum, and the pulse time is 250 ms. In this process, the aluminum source is brought into the chamber in the form of gas and adsorbed on the sample surface to form an active organic aluminum layer. After that, the purge time is 4 s to remove the excess aluminum source that is not adsorbed on the surface. The source temperature of the aluminum source is room temperature. The source temperature of the water source is room temperature, and the pulse time is 250 ms. In this process, water vapor enters the chamber and reacts with the active aluminum source on the sample surface to form an aluminum oxide layer. After that, the purge time is 4 s to remove the excess unadsorbed water source in the chamber. The ALD chamber temperature is 25°C, that is, the entire atomic layer deposition process is carried out at 25°C, and one circle of aluminum oxide is grown according to the above process parameters.

[0087] 6. Preparation of electron transport layer: Fullerene (C60) is deposited on the surface of the passivation layer by thermal evaporation to obtain a fullerene layer with a thickness of 12 nm; tin oxide (SnO2) is deposited on the surface of the fullerene by atomic layer deposition to obtain a tin oxide layer with a thickness of 20 nm. The fullerene layer and the tin oxide layer together constitute the electron transport layer. During the thermal evaporation process, the temperature of the evaporation source is 450°C and the evaporation rate is 0.1 A / s;

[0088] 7. Preparation of the top electrode: IZO is deposited on the surface of the electron transport layer by physical vapor deposition (PVD) to obtain a transparent conductive layer with a thickness of 70 nm; MgF2 is deposited on the surface of the transparent conductive layer by thermal evaporation to obtain an anti-reflection layer with a thickness of 120 nm; finally, silver is deposited on the surface of the anti-reflection layer by thermal evaporation to obtain a 800 nm gate electrode. The transparent conductive layer, anti-reflection layer and gate electrode together constitute the top electrode, and an inverted perovskite solar cell is obtained at the same time.

[0089] Example 2

[0090] The only difference between this embodiment and embodiment 1 is that in this embodiment, two circles of aluminum oxide are grown according to the process parameters of step (5) of embodiment 1, and the thickness of the passivation layer is 0.30 nm.

[0091] Example 3

[0092] The only difference between this embodiment and embodiment 1 is that this embodiment grows three circles of aluminum oxide according to the process parameters of step (5) of embodiment 1, and the thickness of the passivation layer is 0.45 nm.

[0093] Example 4

[0094] The only difference between this embodiment and embodiment 2 is that the passivation layer of this embodiment is Si3N4.

[0095] Example 5

[0096] The only difference between this embodiment and embodiment 2 is that the passivation layer of this embodiment is SiC.

[0097] Example 6

[0098] The only difference between this comparative example and Example 2 is that the passivation layer in this comparative example is tin oxide.

[0099] Comparative Example 1

[0100] The only difference between this comparative example and Example 1 is that this comparative example does not include the preparation of a passivation layer, and the electron transport layer is directly deposited on the surface of the perovskite light absorption layer.

[0101] Comparative Example 2

[0102] The difference between this comparative example and Example 1 is that in this comparative example, four circles of aluminum oxide are grown according to the process parameters of step (5) of Example 1, and the thickness of the passivation layer is 0.60 nm.

[0103] Comparative Example 3

[0104] The difference between this comparative example and Example 1 is that in this comparative example, five circles of aluminum oxide are grown according to the process parameters of step (5) of Example 1, and the thickness of the passivation layer is 0.75 nm.

[0105] Comparative Example 4

[0106] The difference between this comparative example and Example 1 is that in this comparative example, ten circles of aluminum oxide are grown according to the process parameters of step (5) of Example 1, and the thickness of the passivation layer is 1.5 nm.

[0107] Comparative Example 5

[0108] The only difference between this comparative example and Example 2 is that the passivation layer in this comparative example is silicon dioxide.

[0109] Test Case

[0110] Initial performance test of the inverse perovskite solar device: At 25°C and AM 1.5G standard solar spectrum, a solar simulator was used to set the voltage range to 2V to -0.5V, and the current output of the inverse perovskite solar cells prepared in Examples 1-6 and Comparative Examples 1-5 at different voltages was tested, and the corresponding current-voltage (IV) characteristic curves were plotted, where the cell surface area was 1cm 2 , the incident light power (Pin) is 100mW / cm 2 The characteristic curve at this time is the characteristic curve of initial performance, and the initial performance (initial open circuit voltage, initial short circuit current density, initial fill factor and initial photoelectric conversion efficiency) of the inverted perovskite solar cells prepared in Examples 1-6 and Comparative Examples 1-5 are obtained based on the characteristic curve of initial performance.

[0111] (1) Open circuit voltage (Voc): The voltage value corresponding to when the current is equal to zero.

[0112] (2) Short-circuit current density (Jsc): The current value when the voltage is zero is the short-circuit current (Isc), and the current per unit battery surface area is the short-circuit current density.

[0113] (3) Fill factor (FF): The ratio of the maximum output power (Pmax) of the battery to the product of the open circuit voltage and the short circuit current. The calculation formula is (Pmax / Voc*Isc), where the maximum power point is the point where the battery output power reaches its maximum value.

[0114] (4) Photoelectric conversion efficiency (PCE): Photoelectric conversion efficiency refers to the ratio of maximum output power to incident light power (Pin), and the calculation formula is (Pmax / Pin)*100%.

[0115] Aging performance test of trans-perovskite solar cell devices: The trans-perovskite solar cells prepared in Examples 1-6 and Comparative Examples 1-5 were aged for 500 h at 95°C and AM 1.5G in an open circuit. A solar simulator was used to set the voltage range from 2V to -0.5V. The current output of the trans-perovskite solar cells prepared in Examples 1-6 and Comparative Examples 1-5 at different voltages was tested, and the corresponding current-voltage (IV) characteristic curves were plotted. The cell surface area was 1 cm 2 , the incident light power (Pin) is 100mW / cm 2 The characteristic curve at this time is the characteristic curve of aging performance, and the aging performance (open circuit voltage after aging, short circuit current density after aging, fill factor after aging, and photoelectric conversion efficiency after aging) of the inverse perovskite solar cells prepared in Examples 1-6 and Comparative Examples 1-5 is obtained from the characteristic curve of aging performance.

[0116] Efficiency ratio of inverse perovskite solar devices: efficiency ratio = initial photoelectric conversion efficiency / photoelectric conversion efficiency after aging × 100%.

[0117] The test results of the initial performance, aging performance and efficiency ratio of the inverse perovskite solar cells prepared in Examples 1-6 and Comparative Examples 1-5 are shown in Table 1.

[0118] Table 1: Initial performance, aging performance and efficiency ratio of the inverse perovskite solar cells prepared in Examples 1-6 and Comparative Examples 1-5

[0119]

Claims

1. An inverted perovskite solar cell, characterized in that: The inverted perovskite solar cell includes a hole transport layer, a perovskite light absorption layer, a passivation layer and an electron transport layer in sequence from the thickness direction, the passivation layer is selected from one or more of tin oxide, aluminum oxide, silicon nitride and silicon carbide, and the thickness of the passivation layer is 0.15-0.45nm.

2. The inverted perovskite solar cell according to claim 1, characterized in that: The inverse perovskite solar cell has one or more of the following features: The perovskite light absorption layer includes a perovskite structure material, the chemical formula of the perovskite structure material is ABX3, A is a monovalent cation, including but not limited to one or more of cesium ion, rubidium ion, methylamine ion and formamidine ion; B is a divalent cation, including but not limited to one or more of lead ion, copper ion, zinc ion, gallium ion, tin ion and calcium ion; X is a monovalent anion, including but not limited to one or more of iodide ion, bromide ion, chloride ion, fluoride ion, thiocyanate ion, tetrafluoroborate ion and hexafluorophosphate ion; The electron transport layer is C60; The thickness of the hole transport layer is 1-30 nm; The thickness of the perovskite light absorbing layer is 300-3000nm; The thickness of the electron transport layer is 2-30 nm.

3. A method for preparing the inverse perovskite solar cell according to claim 1 or 2, characterized in that: The method comprises the following steps: (1) depositing the perovskite light absorption layer on the surface of the hole transport layer; (2) depositing the passivation layer on the surface of the perovskite light absorbing layer; (3) Depositing the electron transport layer on the surface of the passivation layer to obtain an inverse perovskite solar cell.

4. The method according to claim 3, characterized in that In step (1), the raw material of the perovskite structure material and the solvent are mixed to obtain a perovskite precursor solution, and then the perovskite precursor solution is coated on the surface of the hole transport layer, and then annealed to obtain a perovskite light absorbing layer.

5. The method according to claim 4, characterized in that In step (1), in the perovskite precursor solution, the solvent is selected from one or more of ethanol, isopropanol, methanol, butanol, pentanol, N,N-dimethylformamide, dimethyl sulfoxide, 1,3-dimethyl-3,4,5,6-tetrahydro-2-pyrimidinone, acetonitrile, diphenyl sulfoxide and dimethoxyethanol.

6. The method according to claim 4, characterized in that In step (1), the theoretical concentration of the perovskite structured substance generated in the perovskite precursor solution is 0.1-2.4 mol / L.

7. The method according to claim 4, characterized in that In step (1), the coating method of the perovskite precursor solution is spin coating, blade coating, spray pyrolysis, inkjet printing or slit coating.

8. The method according to claim 3, characterized in that The method has one or more of the following features: In step (2), the deposition method of tin oxide is atomic layer deposition, reactive ion sputtering or chemical vapor deposition; In step (2), the aluminum oxide is deposited by atomic layer deposition; In step (2), the deposition method of nitride and carbide is atomic layer deposition or chemical vapor deposition.

9. The method according to claim 3, characterized in that In step (3), the electron transport layer is deposited by blade coating, slit coating or thermal evaporation.

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