A perovskite solar cell and a method for preparing the same

Abstract

The present invention provides a perovskite solar cell and a preparation method thereof, wherein the perovskite solar cell includes a conductive substrate, an electron transport layer, a perovskite light absorbing layer, a hole transport layer and a metal electrode, wherein the hole transport layer comprises a hole transport layer material and an organic compound having a peroxide bond; the hole transport layer material is selected from any one of Spiro-OMeTAD and PTAA; the organic compound having a peroxide bond is selected from at least one of artemisinin compounds, diacyl peroxides, peroxyesters, peroxycarbonates, and ketone peroxides. The present invention can save the long oxidation time of the hole transport layer, improve the production efficiency of the perovskite solar cell, and enable the perovskite solar cell to have higher photoelectric conversion efficiency and environmental stability.

Description

Technical Field

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

[0002] As an important component of new energy, solar energy plays an important role in the development of human civilization. At present, solar cells are the main way to convert solar energy, so the development of solar cells has attracted much attention worldwide.

[0003] Perovskite solar cells are solar cells that use perovskite-type organic metal halide semiconductors as light-absorbing materials. As a new type of solar cell, it has the advantages of high photoelectric conversion efficiency and low production cost. Perovskite solar cells are usually divided into upright structures and inverted structures. Among them, the upright structure is usually a transparent substrate material, a transparent conductive oxide, an electron transport layer, a perovskite light-absorbing layer, a hole transport layer, and a top electrode from bottom to top, and the inverted structure is usually a transparent substrate material, a transparent conductive oxide, a hole transport layer, a perovskite light-absorbing layer, an electron transport layer, and a top electrode from bottom to top. The upright structure perovskite solar cell usually has a higher photoelectric conversion efficiency. The hole transport layer materials commonly used in the normal structure perovskite solar cells usually include 2,2',7,7'-tetrakis[N,N-di(4-methoxyphenyl)amino]-9,9'-spirobifluorene (i.e., Spiro-OMeTAD, molecular weight 1225.43) and poly[bis(4-phenyl)(2,4,6-trimethylphenyl)amine] (i.e., PTAA). However, when using these materials to prepare the hole transport layer, the hole transport layer needs to be oxidized for a long time to activate or further improve the hole transport performance of the hole transport layer. However, the long-term oxidation requires a lot of time to prepare the hole transport layer, which is not conducive to improving the production efficiency of perovskite solar cells. Summary of the invention

[0004] The purpose of the present invention is to provide a perovskite solar cell and a preparation method thereof, so as to improve the production efficiency of perovskite solar cells, and to improve the photoelectric conversion efficiency and environmental stability of perovskite solar cells. The specific technical scheme is as follows:

[0005] A first aspect of the present invention provides a perovskite solar cell, which comprises a conductive substrate, an electron transport layer, a perovskite light absorbing layer, a hole transport layer and a metal electrode, wherein the hole transport layer comprises a hole transport layer material, a dopant and an organic compound having a peroxide bond;

[0006] The hole transport layer material is selected from any one of Spiro-OMeTAD and PTAA;

[0007] The dopant is selected from at least one of 4-tert-butylpyridine (tBP), lithium bis(trifluoromethylsulfonyl)imide (Li-TFSI), and 4-isopropyl-4'-methyldiphenyl iodide tetrakis(pentafluorophenyl)borate (TPFB);

[0008] The organic compound having a peroxide bond is selected from at least one of artemisinin compounds, diacyl peroxides, peroxyesters, peroxycarbonates, and ketone peroxides;

[0009] The perovskite compound ABX3 in the perovskite light absorbing layer comprises APbI3, wherein A is selected from at least one of MA, FA and Cs.

[0010] In one embodiment of the present invention, the artemisinin compound is selected from at least one of artemisinin, artesunate, dihydroartemisinin, artemether and arteether;

[0011] The diacyl peroxide is selected from at least one of diisobutyl acyl peroxide and diacetyl peroxide;

[0012] The peroxyester is selected from at least one of tert-octyl peroxyester and tert-butyl peroxyester;

[0013] The peroxycarbonate is selected from at least one of di-n-propyl peroxydicarbonate and diethyl peroxydicarbonate;

[0014] The ketone peroxide is selected from at least one of butanone peroxide and acetylacetone peroxide.

[0015] In one embodiment of the present invention, the content of the artemisinin compound in the hole transport layer is 5.9×10 -6 ~7.08×10 -5 mol / cm 3 .

[0016] In one embodiment of the present invention, the APbI3 is selected from at least one of MAPbI3, FAPbI3, and CsPbI3.

[0017] In one embodiment of the present invention, the ABX3 is selected from MAPbI3, FAPbI3, CsPbI3, (MAPbCl3) Y (MAPbI3) 1-Y 、(MAPbBr3) Y (MAPbI3) 1-Y Or at least one of a combination thereof, 0≤Y≤1.

[0018] In one embodiment of the present invention, the perovskite compound further comprises (MAPbCl3) Y (MAPbI3)1-Y 、(MAPbBr3) Y (MAPbI3) 1-Y 、(RbPbCl3) Z (KPbCl3) W 、(RbPbBr3) Z (KPbBr3) W and (RbPbI3) Z (KPbI3) W Or at least one of a combination thereof, 0≤Y≤1, 0≤Z≤0.15, 0≤W≤0.15.

[0019] In one embodiment of the present invention, the conductive substrate is a flexible conductive substrate or a conductive glass substrate;

[0020] The material of the flexible conductive substrate is selected from any one of polyethylene terephthalate, polyphthalamide, polyethylene naphthalate or polyimide;

[0021] The conductive glass substrate is a fluorine-doped tin oxide substrate or an indium-doped tin oxide substrate.

[0022] In one embodiment of the present invention, the electron transport layer is selected from a TiO2 electron transport layer, a SnO2 electron transport layer or a ZnO electron transport layer, and the thickness of the electron transport layer is 20 to 80 nm.

[0023] In one embodiment of the present invention, the metal electrode is selected from any one of an Au electrode, an Ag electrode, an Al electrode or a Cu electrode, and the thickness of the metal electrode is 50 to 100 nm.

[0024] A second aspect of the present invention provides a method for preparing the perovskite solar cell according to the first aspect, comprising:

[0025] preparing an electron transport layer on the surface of a conductive substrate;

[0026] Preparation of perovskite light absorbing layer on the surface of electron transport layer:

[0027] A halide containing A and a halide containing B are added as solutes to a solvent, and stirred for 0.5 to 24 hours to obtain a perovskite precursor liquid, wherein the halide containing A is selected from at least one of formamidine iodide, methylamine iodide or cesium iodide; the halide containing B includes lead iodide, the solvent is selected from at least one of N,N-dimethylformamide (DMF), dimethyl sulfoxide (DMSO), N-methylpyrrolidone (NMP) and γ-butyrolactone, the concentration of the halide containing A is 0.5 to 2.0 mol / L, and the concentration of the halide containing B is 0.5 to 2.0 mol / L;

[0028] Coating a perovskite precursor liquid on the surface of the electron transport layer, and then annealing to obtain a perovskite light absorbing layer, wherein the annealing temperature is 80 to 400° C. and the annealing time is 0.05 to 120 min;

[0029] Preparation of hole transport layer on the surface of perovskite light absorbing layer:

[0030] Adding a hole transport layer material, a dopant, and an organic compound having a peroxide bond into a solvent in a mass ratio of 1:0.16-0.37:0.006-0.9, and stirring for 0.5-24 hours to obtain a hole transport layer precursor liquid;

[0031] The solvent is selected from any one of chlorobenzene and anisole, the dopant is selected from at least one of 4-tert-butylpyridine, lithium bis(trifluoromethylsulfonyl)imide, and 4-isopropyl-4'-methyldiphenyl iodide tetrakis(pentafluorophenyl)borate, and the concentration of the hole transport layer material in the hole transport layer precursor liquid is 24 to 72.3 mg / L;

[0032] Applying the hole transport layer precursor liquid on the surface of the perovskite light absorbing layer to obtain a hole transport layer;

[0033] Preparation of metal electrode on the surface of hole transport layer:

[0034] A metal electrode is evaporated on the surface of the hole transport layer to obtain a perovskite solar cell.

[0035] In one embodiment of the present invention, the film forming methods of the hole transport layer and the perovskite light absorbing layer include: solution spin coating, solution blade coating, slit coating or vapor phase coating.

[0036] In one embodiment of the present invention, the stirring time for preparing the perovskite precursor solution is 10 to 12 hours, the annealing temperature of the perovskite light absorbing layer is 100 to 200° C., and the annealing time is 1 to 60 minutes.

[0037] In one embodiment of the present invention, the perovskite precursor liquid further comprises a perovskite layer dopant, and the perovskite layer dopant comprises at least one of rubidium iodide, potassium iodide, rubidium bromide, potassium bromide, rubidium chloride or potassium chloride;

[0038] The A-containing halide further comprises at least one of methylamine bromide or cesium bromide;

[0039] The B-containing halide further comprises at least one of lead bromide and lead chloride.

[0040] In one embodiment of the present invention, the stirring time when preparing the hole transport layer precursor liquid is 10 to 12 hours.

[0041] In the present invention, the term "mass concentration" refers to the quotient of the mass of a component in a mixture and the total volume of the mixture.

[0042] Beneficial effects of the present invention:

[0043] The present invention provides a perovskite solar cell and a preparation method thereof. The hole transport layer contains an organic compound with a peroxide bond, which can directly oxidize the hole transport layer material. Therefore, there is no need to perform long-term oxidation treatment on the hole transport layer, thereby improving the production efficiency of the perovskite solar cell. In addition, the perovskite solar cell of the present invention has higher photoelectric conversion efficiency and environmental stability.

[0044] Of course, it is not necessary to achieve all of the advantages described above at the same time to implement any product or method of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0045] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0046] Figure 1 It is a schematic diagram of the structure of the perovskite solar cell of the present invention;

[0047] Figure 2 A comparison diagram of photovoltaic JV (current density-voltage) test curves of the perovskite solar cell of Example 1 of the present invention and Comparative Example 1;

[0048] Figure 3 A comparison diagram of photovoltaic JV test curves of the perovskite solar cell of Example 2 of the present invention and Comparative Example 1;

[0049] Figure 4 A comparison diagram of photovoltaic JV test curves of the perovskite solar cell of Example 3 of the present invention and Comparative Example 2;

[0050] Figure 5 This is a comparison diagram of the environmental stability of the perovskite solar cells of Example 1 of the present invention and Comparative Example 1;

[0051] Figure 6 This is a comparison diagram of the environmental stability of the perovskite solar cells of Example 2 of the present invention and Comparative Example 1;

[0052] Figure 7 This is a comparison chart of the environmental stability of the perovskite solar cells of Example 3 of the present invention and Comparative Example 2. DETAILED DESCRIPTION

[0053] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0054] The present invention provides a perovskite solar cell, such as Figure 1 As shown, it includes a conductive substrate 5, an electron transport layer 4, a perovskite light absorption layer 3, a hole transport layer 2 and a metal electrode 1, wherein the hole transport layer contains a hole transport layer material, a dopant and an organic compound having a peroxide bond.

[0055] The hole transport layer material is selected from any one of Spiro-OMeTAD and PTAA. Of course, in addition to the above examples, any substance that belongs to the hole transport layer material belongs to the protection scope of the present invention.

[0056] The dopant may include, but is not limited to, at least one of 4-tert-butylpyridine, lithium bis(trifluoromethylsulfonyl)imide, and 4-isopropyl-4'-methyldiphenyl iodide tetrakis(pentafluorophenyl)borate (TPFB) to enhance the hole transport performance of the hole transport layer.

[0057] In the present invention, the organic compound having a peroxide bond is selected from at least one of artemisinin compounds, diacyl peroxides, peroxyesters, peroxycarbonates, and ketone peroxides.

[0058] The present invention has no particular limitation on perovskite, which may be a perovskite, a composite perovskite or a combination thereof known to those skilled in the art, for example, an ABX3 type perovskite, where ABX3 may contain APbI3, wherein A is selected from at least one of MA, FA and Cs.

[0059] In one embodiment of the present invention, the perovskite compound may further contain at least one of Br or Cl, wherein Br or Cl is usually also used as a dopant.

[0060] The present invention has no particular limitation on artemisinin compounds, for example, the compound may be selected from at least one of artemisinin, artesunate, dihydroartemisinin, artemether and arteether. Of course, in addition to the above examples, any substance belonging to artemisinin compounds falls within the protection scope of the present invention, for example, derivatives of the above artemisinin compounds.

[0061] Among them, the structural formula of artemisinin is:

[0062]

[0063] The structural formula of artesunate is:

[0064]

[0065] The structural formula of dihydroartemisinin is:

[0066]

[0067] The structural formula of artemether is:

[0068]

[0069] The structural formula of artemether is:

[0070]

[0071] Furthermore, the present invention has no particular limitation on the diacyl peroxide (RCOOOOCR'), for example, it can be selected from at least one of diisobutyl acyl peroxide and diacetyl peroxide; the present invention has no particular limitation on the peroxyester (RCOOOR'), for example, it can be selected from at least one of tert-octyl peroxyester and tert-butyl peroxyester; the present invention has no particular limitation on the peroxycarbonate (ROCOOOOCOR'), for example, it can be selected from at least one of di-n-propyl peroxydicarbonate and diethyl peroxydicarbonate; the present invention has no particular limitation on the ketone peroxide (R2C(OOH)2), for example, it can be selected from at least one of butanone peroxide and acetylacetone peroxide.

[0072] The inventors have found that by adding an organic compound with a peroxide bond to the hole transport layer, without being limited to any theory, the hole transport layer material can be directly oxidized to increase the conductivity of the hole transport layer material, and the process of placing it in dry air for a long time in the prior art is omitted, so as to avoid a large number of oxygen molecules in the air from being adsorbed in the hole transport layer, thereby avoiding the migration of oxygen elements in the device during the subsequent operation of the perovskite battery, which leads to a decrease in the stability of the perovskite battery. Artemisinin compounds are usually used to treat diseases such as malaria, but the inventors unexpectedly found that the perovskite solar cell containing artemisinin compounds in the hole transport layer has exceptionally good photoelectric conversion efficiency and environmental stability.

[0073] The inventors found that when the content of artemisinin compounds in the hole transport layer is 5.9×10 -6 ~7.08×10 -5 mol / cm 3 When the perovskite cell is exposed to sunlight, it has excellent photoelectric conversion efficiency and environmental stability.

[0074] In one embodiment of the present invention, the APbI3 is selected from at least one of MAPbI3, FAPbI3, and CsPbI3. MA is methylamine (CH3NH3), and FA is methylamine (CH4N2). Of course, the perovskite of the present invention is not limited to the above examples, as long as the purpose of the present invention can be achieved.

[0075] In one embodiment of the present invention, the perovskite compound may further comprise (MAPbCl3) Y (MAPbI3) 1-Y 、(MAPbBr3) Y (MAPbI3) 1-Y 、(RbPbCl3) Z (KPbCl3) W 、(RbPbBr3) Z (KPbBr3) W and (RbPbI3) Z (KPbI3) W Or at least one of their composites, wherein 0≤Y≤1, 0≤Z≤0.15, 0≤W≤0.15. Of course, the above-mentioned perovskite compound may also include other perovskite compounds containing Rb element or K element in addition to the above-mentioned compounds.

[0076] The present invention has no particular limitation on the conductive substrate, and any conductive substrate known in the art can be used as long as the purpose of the present invention can be achieved. For example, the conductive substrate may include a flexible conductive substrate or a conductive glass substrate, wherein the flexible conductive substrate may be a fluorine-doped tin oxide (FTO) flexible conductive substrate or an indium-doped tin oxide (ITO) flexible conductive substrate; the conductive glass substrate may be a rigid transparent substrate, such as a FTO conductive glass substrate or an ITO conductive glass substrate.

[0077] It can be understood that the electron transport layer, perovskite light absorbing layer, hole transport layer and metal electrode of the present invention can be formed layer by layer on a conductive substrate. For example, the perovskite solar cell of the present invention can be formed by stacking from bottom to top according to the conductive substrate-electron transport layer-perovskite light absorbing layer-hole transport layer-metal electrode.

[0078] In one embodiment of the present invention, the material of the flexible conductive substrate can be selected from any one of polyethylene terephthalate (PET), polyphthalamide (PPA), polyethylene naphthalate (PEN) or polyimide (PI).

[0079] The present invention has no particular limitation on the material of the electron transport layer, which may be a material or a combination thereof known to those skilled in the art, for example, it may be selected from a titanium dioxide (TiO2) electron transport layer, a tin dioxide (SnO2) electron transport layer, or a zinc oxide (ZnO) electron transport layer, etc. Moreover, the present invention has no particular limitation on the thickness of the electron transport layer, as long as the purpose of the present invention can be achieved, for example, the thickness of the electron transport layer may be 20 to 80 nm.

[0080] The present invention has no particular limitation on the material of the metal electrode, which may be a material or a combination thereof known to those skilled in the art, such as a gold (Au) electrode, an Ag electrode, an Al electrode or a Cu electrode. Furthermore, the present invention has no particular limitation on the thickness of the metal electrode, as long as the purpose of the present invention can be achieved, such as 50 to 100 nm. Electrode thickness within this range can achieve better results. Of course, those skilled in the art can select a suitable electrode thickness as needed.

[0081] As required, the perovskite solar cell of the present invention may further include other layers. For example, a conductive layer may be provided on a conductive substrate, and electrodes may be respectively drawn out from the conductive layer and the metal electrode to form a circuit.

[0082] The present invention provides a perovskite solar cell, in which a hole transport layer contains an organic compound having a peroxide bond, which can directly oxidize the hole transport layer material, thereby eliminating the need for long-term oxidation treatment of the hole transport layer, thereby improving the production efficiency of the perovskite solar cell, and the perovskite solar cell of the present invention has higher photoelectric conversion efficiency and environmental stability.

[0083] The present invention also provides a method for preparing a perovskite solar cell, comprising the following steps:

[0084] preparing an electron transport layer on the surface of a conductive substrate;

[0085] Preparation of perovskite light absorbing layer on the surface of electron transport layer:

[0086] Adding A-containing halide and B-containing halide as solutes into a solvent and stirring for 0.5 to 24 hours to obtain a perovskite precursor liquid, wherein the A-containing halide is selected from at least one of formamidine iodide, methylamine iodide, or cesium iodide; the B-containing halide includes lead iodide, the solvent is selected from at least one of DMF, DMSO, NMP and γ-butyrolactone, the concentration of the A-containing halide is 0.5 to 2.0 mol / L, and the concentration of the B-containing halide is 0.5 to 2.0 mol / L;

[0087] Coating a perovskite precursor liquid on the surface of the electron transport layer, and then annealing to obtain a perovskite light absorbing layer, wherein the annealing temperature is 80 to 400° C. and the annealing time is 0.05 to 120 min;

[0088] Preparation of hole transport layer on the surface of perovskite light absorbing layer:

[0089] Adding a hole transport layer material, a dopant, and an organic compound having a peroxide bond into a solvent in a mass ratio of 1:1:0.16-0.37:0.006-0.9, and stirring for 0.5-24 hours to obtain a hole transport layer precursor liquid;

[0090] The solvent is selected from any one of chlorobenzene and anisole, the dopant is selected from at least one of 4-tert-butylpyridine (tBP), lithium bis(trifluoromethylsulfonyl)amide (Li-TFSI), and 4-isopropyl-4'-methyldiphenyl iodide tetrakis(pentafluorophenyl)borate (TPFB), and the concentration of the hole transport layer material in the hole transport layer precursor liquid is 24 to 72.3 mg / L. The dopant can further improve the hole transport performance of the hole transport layer.

[0091] Applying the hole transport layer precursor liquid on the surface of the perovskite light absorbing layer to obtain a hole transport layer;

[0092] Preparation of metal electrode on the surface of hole transport layer:

[0093] A metal electrode is evaporated on the surface of the hole transport layer to obtain a perovskite solar cell.

[0094] The inventor has found that the hole transport layer precursor liquid containing an organic compound having a peroxide bond prepared by the present invention, wherein the organic compound having a peroxide bond has a strongly oxidizing peroxide bond in its molecular structure, which can directly oxidize the hole transport layer material, thereby being able to save the prior art, the process of long-term oxidation in dry air after the hole transport layer is prepared, and the above-mentioned organic compound having a peroxide bond can further enhance the hole transport performance of the hole transport layer material, and the organic groups such as carbonyl and carboxyl in the organic compound having a peroxide bond can passivate the surface defects of the contact surface between the perovskite light absorption layer and the hole transport layer, thereby further improving the photoelectric conversion efficiency of the perovskite solar cell. In addition, there are a large number of hydrocarbon groups in the above-mentioned organic compound having a peroxide bond, which has excellent hydrophobicity, so the humidity stability of the perovskite solar cell can be further improved, that is, the preparation method of the present invention can not only improve the production efficiency of perovskite solar cells, but also improve the photoelectric conversion efficiency and environmental stability of perovskite solar cells.

[0095] The present invention has no particular limitation on the preparation process of the hole transport layer, and for example, a solution spin coating method, a solution blade coating method, a slit coating method or a vapor phase method may be used.

[0096] The present invention has no particular limitation on the preparation process of the electron transport layer, and for example, a solution spin coating method, a solution scraping method, a solution spraying method, a slit coating method or a hydrothermal growth method may be used.

[0097] The present invention has no particular limitation on the preparation process of the perovskite light absorbing layer, for example, a solution spin coating method, a solution scraping method, a slit coating method or a steam method may be used.

[0098] Of course, the film forming processes of the electron transport layer, the perovskite light absorbing layer, and the hole transport layer of the present invention may include but are not limited to the examples given above, as long as the purpose of the present invention can be achieved.

[0099] In one embodiment of the present invention, the stirring time for preparing the perovskite precursor liquid is preferably 10 to 12 hours, the annealing temperature of the perovskite light absorbing layer is preferably 100 to 200° C., and the annealing time is preferably 1 to 60 minutes. The prepared perovskite solar cell has higher photoelectric conversion efficiency and better environmental stability.

[0100] In one embodiment of the present invention, the organic compound having a peroxide bond is preferably an artemisinin compound, and the resulting perovskite solar cell has higher photoelectric conversion efficiency and higher environmental stability.

[0101] In one embodiment of the present invention, the perovskite precursor liquid further comprises a perovskite layer dopant, and the perovskite layer dopant includes at least one of rubidium iodide, potassium iodide, rubidium bromide, potassium bromide, rubidium chloride or potassium chloride; the A-containing halide may also comprise at least one of methylammonium bromide or cesium bromide, wherein methylammonium bromide or cesium bromide exists in a small amount of doped form; the B-containing halide further comprises at least one of lead bromide and lead chloride.

[0102] In one embodiment of the present invention, the stirring time during the preparation of the hole transport layer precursor liquid is 10 to 12 hours, which can make the solutes in the hole transport layer precursor liquid more evenly mixed.

[0103] The following examples and comparative examples are given to more specifically describe the embodiments of the present invention. Various tests and evaluations were performed according to the following methods. In addition, unless otherwise specified, "parts" and "%" are weight references.

[0104] Example 1

[0105] <Preparation of Conductive Substrate>

[0106] The commercially available indium-doped tin oxide PEN flexible conductive substrate (model Peccell) was cut into 20mm×20mm sheets, etched and rinsed, and then placed in a polytetrafluoroethylene cleaning rack, and then ultrasonically cleaned for 15 minutes with deionized water, ethanol, and isopropanol, respectively, and then the cleaning rack containing the conductive substrate was placed in an oven for drying and standby use. The thickness of the conductive substrate is about 140nm. Etching can prevent the upper and lower electrodes from being short-circuited during device testing.

[0107] <Preparation of Electron Transport Layer>

[0108] 1 mL of hydrocolloid SnO2 dispersion was added to a reagent bottle, and then 6 mL of deionized water was added to the reagent bottle. After ultrasonic dispersion for 15 minutes, a SnO2 dispersion was obtained, wherein the mass concentration of the hydrocolloid SnO2 dispersion was 15%;

[0109] The dried PEN flexible conductive substrate was placed in a preheated UV-ozone cleaning machine for 15 minutes and then taken out for use;

[0110] SnO2 electron transport layer film was prepared by spin coating:

[0111] 90 μL of SnO2 dispersion was dripped onto the surface of the treated PEN flexible conductive substrate, the spin coating speed was controlled to 3000 rpm, the spin coating time was 30 s, to obtain a SnO2 wet film, and then annealed at 120°C for 30 min to obtain an electron transport layer with SnO2 and a thickness of 40 nm.

[0112] <Preparation of perovskite precursor solution>

[0113] The halide containing A, formamidine iodide, methylamine bromide, cesium iodide, and the halide containing B, lead iodide and lead bromide, are added as solutes into a solvent consisting of DMF and DMSO, and then artemisinin is added. After magnetic stirring for 12 hours, a perovskite precursor solution is obtained.

[0114] Among them, the volume of DMF is 800 μL, the volume of DMSO is 200 μL, the concentration of formamidine iodide in the perovskite precursor liquid is 1.0 mol / L, the concentration of methylammonium bromide in the perovskite precursor liquid is 0.2 mol / L, the concentration of cesium iodide in the perovskite precursor liquid is 0.13 mol / L, and the concentration of the A-containing halide in the perovskite precursor liquid is 1.33 mol / L.

[0115] The concentration of lead iodide in the perovskite precursor liquid is 1.1 mol / L, the concentration of lead bromide in the perovskite precursor liquid is 0.2 mol / L, and the concentration of the B-containing halide in the perovskite precursor liquid is 1.3 mol / L.

[0116] <Preparation of perovskite light-absorbing layer>

[0117] The sheet with SnO2 electron transport layer was treated with UV ozone for 10 minutes, and then 50 μL of perovskite precursor liquid was dripped on the surface of the sheet to cover the entire surface. The perovskite light absorption layer was prepared by spin coating. The spin coating process was first spin coating at 800 rpm for 10 seconds, and then spin coating at 4000 rpm for 30 seconds to obtain a perovskite precursor wet film. 200 μL of chlorobenzene was dripped in the last 3 seconds of spin coating, and then placed on a hot plate at 120°C for heating and annealing for 30 minutes to obtain a perovskite light absorption layer with a thickness of about 500 nm. Among them, chlorobenzene, as an anti-solvent, can extract the solvent in the perovskite precursor wet film, so that the perovskite precursor nucleates and crystallizes.

[0118] <Preparation of hole transport layer>

[0119] Add 72.3 mg of Spiro-OMeTAD powder to a 5 mL reagent bottle, add 17.5 μL of Li-TFSI acetonitrile solution, add 28.8 μL of tBP, add 0.80 mg of artemisinin, and then add 1 mL of chlorobenzene, cover and stir for 0.5 h to obtain a mixed solution. The concentration of Li-TFSI in acetonitrile is 520 mg / mL;

[0120] The mixed solution was coated on the surface of the perovskite light-absorbing layer, and a hole transport layer was prepared by spin coating. The spin coating process was 3000 rpm for 30 seconds. After the spin coating was completed, a hole transport layer was obtained with a thickness of about 250 nm.

[0121] <Preparation of Metal Electrode>

[0122] The sheet with the hole transport layer was placed on a thermal evaporator at 2×10 -4 100 nm of Au was evaporated under a vacuum degree of Pa to obtain a metal electrode, completing the preparation of the perovskite solar cell.

[0123] Example 2

[0124] Except that artesunate is selected as the artemisinin compound and the added amount of artesunate is 1.09 mg, the rest is the same as Example 1.

[0125] Example 3

[0126] The method is the same as Example 1 except that PTAA is used as the hole transport layer material, the amount of PTAA is 20 mg, the amount of artemisinin added is 0.80 mg, and TPFB is used as the dopant, the amount of TPFB added is 3.84 mg.

[0127] Example 4

[0128] The method is the same as Example 1 except that the artemisinin compound is dihydroartemisinin, the amount of dihydroartemisinin added is 0.40 mg, the preparation process of the perovskite precursor liquid is different, the annealing temperature when preparing the perovskite light absorbing layer is 80° C., and the annealing time is 120 min.

[0129] The preparation process of perovskite precursor liquid is:

[0130] The formamidine iodide and cesium iodide containing the A halide, and the lead iodide containing the B halide are added as solutes into a solvent consisting of DMF and DMSO, and magnetically stirred for 24 hours to obtain a perovskite precursor solution.

[0131] Among them, the volume of DMF is 800 μL, the volume of DMSO is 200 μL, the concentration of formamidine iodide in the perovskite precursor liquid is 0.85 mol / L, the concentration of cesium iodide in the perovskite precursor liquid is 0.15 mol / L, that is, the concentration of the A-containing halide in the perovskite precursor liquid is 1.0 mol / L.

[0132] The concentration of lead iodide in the perovskite precursor solution is 1.0 mol / L, that is, the concentration of the B-containing halide in the perovskite precursor solution is 1.0 mol / L.

[0133] Example 5

[0134] The method is the same as Example 1 except that artemisinin is used as the artemisinin-based compound, the amount of artemisinin added is 2.40 mg, the stirring time for preparing the hole transport layer precursor liquid is 10 h, the preparation process of the perovskite precursor liquid is different, the solvent in the perovskite precursor liquid is a mixture of DMF and NMP, the annealing temperature for preparing the perovskite light absorbing layer is 400° C., and the annealing time is 0.05 min.

[0135] The halide containing A, formamidine iodide and methylamine bromide, and the halide containing B, lead iodide and lead bromide are added as solutes into a solvent consisting of DMF and NMP, and magnetic stirring is performed for 0.5 h to obtain a perovskite precursor solution.

[0136] Among them, the volume of DMF is 800 μL, the volume of NMP is 200 μL, the concentration of formamidine iodide in the perovskite precursor liquid is 1.7 mol / L, the concentration of methylammonium bromide in the perovskite precursor liquid is 0.3 mol / L, and the concentration of the A-containing halide in the perovskite precursor liquid is 2.0 mol / L.

[0137] The concentration of lead iodide in the perovskite precursor liquid is 1.7 mol / L, the concentration of lead bromide in the perovskite precursor liquid is 0.3 mol / L, and the concentration of the B-containing halide in the perovskite precursor liquid is 2.0 mol / L.

[0138] Example 6

[0139] Except that the halide containing A is methylamine iodide and the halide containing B is lead iodide, the rest is the same as Example 1.

[0140] Example 7

[0141] The invention is the same as Example 1 except that artemisinin-based compound is artemisinin, the amount of artemisinin added is 0.85 mg, the stirring time for preparing the hole transport layer precursor liquid is 24 h, the solvent in the perovskite precursor liquid is a mixture of DMSO and γ-butyrolactone, the annealing temperature for preparing the perovskite light absorbing layer is 200° C., and the annealing time is 1 min.

[0142] Example 8

[0143] The above method is the same as Example 1 except that artemisinin-based compound is selected as artemisinin, the addition amount of artemisinin is 0.89 mg, the stirring time for preparing the hole transport layer precursor liquid is 12 h, the annealing temperature for preparing the perovskite light absorbing layer is 100° C., and the annealing time is 60 min.

[0144] Example 9

[0145] The process is the same as that of Example 1 except that the organic compound having a peroxide bond is diisobutyl acyl peroxide and the added amount of diisobutyl acyl peroxide is 0.49 mg.

[0146] Example 10

[0147] The process is the same as that of Example 1 except that the organic compound having a peroxide bond is tert-octyl peroxy ester and the added amount of tert-octyl peroxy ester is 0.46 mg.

[0148] Embodiment 11

[0149] The process is the same as that of Example 1 except that the organic compound having a peroxide bond is di-n-propyl peroxydicarbonate and the added amount of di-n-propyl peroxydicarbonate is 0.58 mg.

[0150] Example 12

[0151] The process is the same as that of Example 1 except that the organic compound having a peroxide bond is butanone peroxide and the amount of butanone peroxide added is 0.60 mg.

[0152] Comparative Example 1

[0153] Except that the perovskite precursor liquid does not contain an organic compound having a peroxide bond, the rest is the same as Example 1.

[0154] Comparative Example 2

[0155] Except that the perovskite precursor solution does not contain an organic compound having a peroxide bond, the rest is the same as Example 3.

[0156] The preparation data and performance parameters of each embodiment and each comparative example are shown in Table 1.

[0157] Table 1 Preparation data and performance parameters of each embodiment and comparative example

[0158]

[0159]

[0160] <Performance Test>

[0161] Perovskite cell photoelectric conversion efficiency test:

[0162] The current density (J)-voltage (V) of the perovskite cell was measured using a solar simulator (Newport Oriel, USA) and a digital source meter (Keithley 2420, USA). The photovoltaic JV test curves of each embodiment and comparative example are shown in FIG. Figure 2 , Figure 3 , Figure 4 shown.

[0163] Perovskite battery long-term PCE (Power Conversion Efficiency) stability test:

[0164] The perovskite solar cells prepared in each embodiment and each comparative example were placed in a room temperature 15% relative humidity environment for 600 hours, and the ratio of the energy conversion efficiency after being placed in the above thermal environment to the energy conversion efficiency before being placed in the above environment was tested as a stability evaluation parameter.

[0165] Figure 2 : is a comparison diagram of photovoltaic JV test curves of the perovskite solar cell of Example 1 and Comparative Example 1, as shown in Figure 2 As shown, the photoelectric conversion efficiency of the perovskite solar cell in Example 1 of the present invention is significantly improved compared with that in Comparative Example 1.

[0166] Figure 3 : is a comparison diagram of the photovoltaic JV test curves of the perovskite solar cell of Example 2 and Comparative Example 1, as shown in Figure 3 As shown, the photoelectric conversion efficiency of the perovskite solar cell in Example 2 of the present invention is significantly improved compared with that in Comparative Example 1.

[0167] Figure 4 3 is a comparison diagram of the photovoltaic JV test curves of the perovskite solar cell of Example 3 and Comparative Example 2, as shown in FIG. Figure 4 As shown, the photoelectric conversion efficiency of the perovskite solar cell of Example 3 of the present invention is significantly improved compared with that of Comparative Example 2.

[0168] Figure 5 : is a comparison chart of the environmental stability of the perovskite solar cell of Example 1 and Comparative Example 1, as shown in Figure 5 As shown, the environmental stability performance of the perovskite solar cell in Example 1 of the present invention is significantly improved compared with that in Comparative Example 1.

[0169] Figure 6 : is a comparison chart of the environmental stability of the perovskite solar cell of Example 2 and Comparative Example 1, as shown in Figure 6 As shown, the environmental stability performance of the perovskite solar cell in Example 2 of the present invention is significantly improved compared with that in Comparative Example 1.

[0170] Figure 7 3 is a comparison chart of the environmental stability of the perovskite solar cells of Example 3 and Comparative Example 2. Figure 7 As shown, the environmental stability performance of the perovskite solar cell in Example 3 of the present invention is significantly improved compared with that in Comparative Example 2.

[0171] From the data in Table 1, it can be seen that although the photoelectric conversion efficiency of comparative example 1 is high, its environmental stability is poor, and although the environmental stability of comparative example 2 is good, the photoelectric conversion efficiency is low. The photoelectric conversion efficiency and environmental stability of embodiments 1, 2, 4 to 12 of the present invention are significantly improved compared with comparative example 1; the environmental stability of embodiment 3 is significantly improved compared with comparative example 1, and the photoelectric conversion efficiency and environmental stability of embodiment 3 are significantly improved compared with comparative example 2, especially the photoelectric conversion efficiency is improved by more than 30%; the photoelectric conversion efficiency and environmental stability of embodiments 1 to 12 are significantly improved compared with comparative example 2. In summary, by adding an organic compound having a peroxide bond to the hole transport layer, the perovskite solar cell can have higher photoelectric conversion efficiency and environmental stability. When the organic compound having a peroxide bond is an artemisinin compound, the performance of the perovskite solar cell is better.

[0172] The above description is only a preferred embodiment of the present invention and is not intended to limit the protection scope of the present invention. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention are included in the protection scope of the present invention.

Claims

1. A perovskite solar cell comprising a conductive substrate, an electron transport layer, a perovskite light absorbing layer, a hole transport layer and a metal electrode, wherein: The hole transport layer comprises a hole transport layer material, a dopant and an organic compound having a peroxide bond; The hole transport layer material is selected from any one of Spiro-OMeTAD and PTAA; The dopant is selected from at least one of 4-tert-butylpyridine, lithium bis(trifluoromethylsulfonyl)imide, and 4-isopropyl-4'-methyldiphenyl iodide tetrakis(pentafluorophenyl)borate; The organic compound having a peroxide bond is an artemisinin compound, and the artemisinin compound is at least one selected from artemisinin, artesunate, dihydroartemisinin, artemether and arteether; The perovskite compound ABX3 in the perovskite light absorbing layer comprises APbI3, wherein A is selected from at least one of MA, FA and Cs.

2. The perovskite solar cell according to claim 1, wherein: The content of the artemisinin compound in the hole transport layer is 5.9×10 -6 ~7.08×10 -5 mol / cm 3 .

3. The perovskite solar cell according to claim 1, wherein: The APbI3 is selected from at least one of MAPbI3, FAPbI3, and CsPbI3.

4. The perovskite solar cell according to claim 1, wherein: The perovskite compound further comprises (MAPbCl3) Y (MAPbI3) 1-Y 、(MAPbBr3) Y (MAPbI3) 1-Y 、(RbPbCl3) Z (KPbCl3) W 、(RbPbBr3) Z (KPbBr3) W and (RbPbI3) Z (KPbI3) W Or at least one of a combination thereof, 0≤Y≤1, 0≤Z≤0.15, 0≤W≤0.

15.

5. The perovskite solar cell according to claim 1, wherein: The conductive substrate is a flexible conductive substrate or a conductive glass substrate; The material of the flexible conductive substrate is selected from any one of polyethylene terephthalate, polyphthalamide, polyethylene naphthalate or polyimide; The conductive glass substrate is a fluorine-doped tin oxide substrate or an indium-doped tin oxide substrate.

6. A method for preparing a perovskite solar cell according to any one of claims 1 to 5, the method comprising: preparing an electron transport layer on the surface of a conductive substrate; Preparation of perovskite light absorbing layer on the surface of electron transport layer: Adding A-containing halide and B-containing halide as solutes to a solvent and stirring for 0.5 to 24 hours to obtain a perovskite precursor liquid, wherein the A-containing halide is selected from at least one of formamidine iodide, methylamine iodide or cesium iodide; the B-containing halide includes lead iodide, the solvent is selected from at least one of N,N-dimethylformamide, dimethyl sulfoxide, N-methylpyrrolidone and γ-butyrolactone, the concentration of the A-containing halide is 0.5 to 2.0 mol / L, and the concentration of the B-containing halide is 0.5 to 2.0 mol / L; Coating a perovskite precursor liquid on the surface of the electron transport layer, and then annealing to obtain a perovskite light absorbing layer, wherein the annealing temperature is 80 to 400° C. and the annealing time is 0.05 to 120 min; Preparation of hole transport layer on the surface of perovskite light absorbing layer: Adding a hole transport layer material, a dopant, and an organic compound having a peroxide bond into a solvent in a mass ratio of 1:0.16-0.37:0.006-0.9, and stirring for 0.5-24 hours to obtain a hole transport layer precursor liquid; The solvent is selected from any one of chlorobenzene and anisole, the dopant is selected from at least one of 4-tert-butylpyridine, lithium bis(trifluoromethylsulfonyl)imide, and 4-isopropyl-4'-methyldiphenyl iodide tetrakis(pentafluorophenyl)borate, and the concentration of the hole transport layer material in the hole transport layer precursor liquid is 24 to 72.3 mg / L; Applying the hole transport layer precursor liquid on the surface of the perovskite light absorbing layer to obtain a hole transport layer; Preparation of metal electrode on the surface of hole transport layer: A metal electrode is evaporated on the surface of the hole transport layer to obtain a perovskite solar cell.

7. The method for preparing a perovskite solar cell according to claim 6, wherein the film forming method of the hole transport layer and the perovskite light absorbing layer comprises: Solution spin coating, solution blade coating, slot coating or vapor phase method.

8. The method for preparing a perovskite solar cell according to claim 6, wherein the stirring time for preparing the perovskite precursor liquid is 10 to 12 hours, the annealing temperature of the perovskite light absorbing layer is 100 to 200°C, and the annealing time is 1 to 60 minutes.

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