Solar cell and preparation method thereof, electric equipment and power generation equipment

Abstract

The invention provides a solar cell and a preparation method thereof, electric equipment and power generation equipment. The preparation method comprises the following steps: providing a substrate; one side of the substrate is coated with a charge transfer solution, a first charge transfer layer is obtained through curing, and the charge transfer solution comprises a first charge transfer material and organic amine salt; forming a perovskite inorganic layer on one side, far away from the substrate, of the first charge transport layer, wherein the material of the perovskite inorganic layer comprises lead halide; forming a perovskite organic layer on one side, far away from the substrate, of the perovskite inorganic layer; and annealing the perovskite inorganic layer and the perovskite organic layer to obtain the perovskite light absorption layer. Defects of a bottom interface can be reduced, the perovskite crystal quality is improved, and the photoelectric conversion efficiency of the solar cell is improved on the whole.

Description

Technical Field

[0001] The present invention relates to the field of battery technology, and in particular to a solar cell and a preparation method thereof, an electrical device and a power generation device. Background Art

[0002] Perovskite / crystalline silicon (PVK / Si) stacked cells are regarded as a new type of high-efficiency photovoltaic technology due to their ultra-high conversion efficiency. The conformal preparation of perovskite top cells on industrialized suede crystalline silicon cells has the advantages of high current density, process matching and high compatibility. Usually, the two-step evaporation and solution method or the full evaporation method is used to conformally prepare perovskite top cells on suede bottom cells. However, these two methods have problems such as incomplete reaction of organic salt and inorganic salt components at the bottom interface and the presence of free metal ions, which leads to poor quality of perovskite crystals at the bottom interface and many interface defects. Summary of the invention

[0003] The present invention aims to solve at least one of the technical problems in the related art to a certain extent. To this end, one object of the present invention is to provide a method for preparing a solar cell, wherein the perovskite grains in the solar cell prepared by the method have better quality and better photoelectric conversion efficiency.

[0004] In the first aspect of the present invention, the present invention provides a method for preparing a solar cell. According to an embodiment of the present invention, the method for preparing a solar cell comprises: providing a substrate; coating a charge transport solution on one side of the substrate, and curing to obtain a first charge transport layer, wherein the charge transport solution comprises a first charge transport material and an organic amine salt; forming a perovskite prefabricated layer on a side of the first charge transport layer away from the substrate, wherein the perovskite prefabricated layer comprises an inorganic salt and an organic salt, wherein the inorganic salt comprises a halide salt; and annealing the perovskite prefabricated layer to obtain a perovskite light absorbing layer. Thus, by adding an organic ammonium salt to the charge transport solution, an organic ammonium salt is distributed on the surface of the first charge transport layer formed away from the substrate (or the interface between the first charge transport layer and the perovskite prefabricated layer), and the organic ammonium salt can react with a halide salt such as lead halide in the subsequent perovskite prefabricated layer to eliminate residual lead ions at the bottom interface of the perovskite light absorbing layer (i.e., the surface of the perovskite light absorbing layer close to the first charge transport layer), thereby reducing the defects of the bottom interface; at the same time, the organic ammonium salt reacts with the inorganic salt in the perovskite prefabricated layer at the bottom interface to generate a perovskite material, and the perovskite material can be used as a seed layer to induce the subsequent inorganic salt and organic salt to react and grow the perovskite material, thereby improving the sufficiency of the reaction of the perovskite inorganic salt and the organic salt, and improving the perovskite crystallization quality, thereby improving the photoelectric conversion efficiency of the solar cell as a whole, while improving the yield and reproducibility of the battery.

[0005] According to an embodiment of the present invention, the organic amine salt includes at least one of formamidine hydroiodide, formamidine hydrobromide, formamidine hydrochloride, methylamine hydroiodide, methylamine hydrobromide, methylamine hydrochloride, phenylethylamine hydroiodide, phenylethylamine hydrobromide, phenylethylamine hydrochloride, ethylenediamine hydroiodide, ethylenediamine hydrobromide, ethylenediamine hydrochloride, propylenediamine hydroiodide, propylenediamine hydrobromide, propylenediamine hydrochloride, butylene diamine hydroiodide, butylene diamine hydrobromide, butylene diamine hydrochloride, oleylamine hydroiodide, oleylamine hydrobromide, oleylamine hydrochloride, 2-thiopheneethylamine hydroiodide, 2-thiopheneethylamine hydrobromide or 2-thiopheneethylamine hydrochloride.

[0006] According to an embodiment of the present invention, the molar ratio of the organic ammonium salt to the first charge transport material in the charge transport solution is 0.001 to 0.1.

[0007] According to an embodiment of the present invention, the total molar concentration of the organic ammonium salt and the first charge transport material in the charge transport solution is 0.05 to 1 mmol / mL.

[0008] According to an embodiment of the present invention, the first charge transport layer is a self-assembled hole transport layer.

[0009] According to an embodiment of the present invention, the first charge transport material includes at least one of [4-(3,6-dimethoxy-9H-carbazole-9-yl)butyl]phosphonic acid, (4-(3,6-dimethyl-9H-carbazole-9-yl)butyl)phosphonic acid, [4-(9H-carbazole-9-yl)butyl]phosphonic acid, (4-(3,6-dibromo-9H-carbazole-9-yl)butyl)phosphonic acid, [2-(3,6-dimethoxy-9H-carbazole-9-yl)ethyl]phosphonic acid, (2-(3,6-dimethyl-9H-carbazole-9-yl)ethyl)phosphonic acid, (2-(9H-carbazole-9-yl)ethyl)phosphonic acid, (2-(3,6-dibromo-9H-carbazole-9-yl)ethyl)phosphonic acid, and [4-(7H-dibenzocarbazole-7-yl)butyl]phosphonic acid.

[0010] According to an embodiment of the present invention, the method of coating the charge transport solution includes one of a spin coating method, a blade coating method, a slit coating method, an inkjet printing method, and an ultrasonic spray method.

[0011] According to an embodiment of the present invention,

[0012] The method for preparing the perovskite prefabricated layer includes: using a co-evaporation method to evaporate the inorganic salt and the organic salt on the side of the first charge transport layer away from the substrate, or the method for preparing the perovskite prefabricated layer includes: first depositing the inorganic salt on the side of the first charge transport layer away from the substrate by an evaporation method to form the perovskite inorganic layer; and then depositing the organic salt on the surface of the perovskite inorganic layer away from the substrate by an evaporation method to form the perovskite organic layer, or coating the surface of the perovskite inorganic layer away from the substrate by a solution method. An organic salt solution is applied to form the perovskite organic layer.

[0013] According to an embodiment of the present invention, the inorganic salt includes at least one of PbI2, PbBr2 or PbCl2, and at least one of CsI, CsBr or CsCl; the organic salt includes at least one of formamidine hydroiodide, formamidine hydrobromide, formamidine hydrochloride, methylammonium iodide, methylammonium bromide or methylammonium chloride.

[0014] According to an embodiment of the present invention, the substrate is a transparent electrode layer; or, the substrate includes a bottom battery and the transparent electrode layer located on the surface of the bottom battery, and the charge transfer solution is coated on the surface of the transparent electrode layer away from the bottom battery.

[0015] According to an embodiment of the present invention, the bottom cell comprises a crystalline silicon cell, and the surface of the crystalline silicon cell close to the transparent electrode layer is a velvet surface.

[0016] According to an embodiment of the present invention, the method for preparing a solar cell further includes: forming a second charge transport layer on a side of the perovskite light absorbing layer away from the substrate; and forming an electrode on a side of the second charge transport layer away from the substrate.

[0017] In another aspect of the present invention, the present invention provides a solar cell, according to an embodiment of the present invention. The solar cell is prepared by the method described above. Thus, the solar cell has a better energy conversion efficiency. Those skilled in the art can understand that the solar cell has all the features and advantages of the method for preparing a solar cell described above, and no further elaboration is given here.

[0018] In another aspect of the present invention, the present invention provides an electric device. According to an embodiment of the present invention, the electric device includes the solar cell described above. Thus, the electric device has good power usage performance. Those skilled in the art can understand that the electric device has all the features and advantages of the solar cell described above, and no further elaboration is given here.

[0019] In another aspect of the present invention, the present invention provides a power generation device. According to an embodiment of the present invention, the power generation device includes the solar cell described above. Thus, the power generation device has good power generation efficiency. Those skilled in the art can understand that the power generation device has all the features and advantages of the solar cell described above, and no further elaboration is given here. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] The above and / or additional aspects and advantages of the present invention will become apparent and easily understood from the description of the embodiments in conjunction with the following drawings, in which:

[0021] Figure 1 is a schematic diagram of a process for preparing a solar cell in one embodiment of the present invention;

[0022] Figure 2 is a schematic diagram of preparing a perovskite light-absorbing layer in another embodiment of the present invention;

[0023] Figure 3 is a schematic diagram of preparing a perovskite light-absorbing layer in another embodiment of the present invention;

[0024] Figure 4 It is a schematic structural diagram of a solar cell in another embodiment of the present invention.

[0025] Reference numerals: substrate 10 ; first charge transport layer 21 ; perovskite pre-layer 3 ; perovskite inorganic layer 31 ; perovskite organic layer 32 ; perovskite light absorbing layer 30 ; second charge transport layer 22 ; buffer layer 40 ; electrode 50 . DETAILED DESCRIPTION

[0026] The scheme of the present invention will be explained below in conjunction with the embodiments. It will be appreciated by those skilled in the art that the following embodiments are only used to illustrate the present invention and should not be considered as limiting the scope of the present invention. Where specific techniques or conditions are not indicated in the embodiments, the techniques or conditions described in the literature in this area or the product specifications are used. The reagents or instruments used are not indicated by the manufacturer and are all conventional products that can be obtained commercially.

[0027] The present invention is described below with reference to specific embodiments. It should be noted that these embodiments are merely illustrative and do not limit the present invention in any way.

[0028] In a first aspect of the present invention, the present invention provides a method for preparing a solar cell. Figure 1 and Figure 2 , the method for preparing a solar cell comprises:

[0029] S100: providing a substrate 10.

[0030] According to some embodiments of the present invention, the solar cell prepared by the method can be a single-junction perovskite cell, in which case the substrate is a transparent electrode layer (transparent conductive oxide, such as indium tin oxide (ITO), indium zinc oxide (IZO), tungsten-doped indium oxide (IWO) and aluminum-doped zinc oxide (AZO), serving as the transparent electrode of the solar cell.

[0031] According to other embodiments of the present invention, the solar cell prepared by the method can be a stacked cell containing a perovskite cell. In some embodiments, the substrate includes a bottom cell and a transparent electrode layer located on the surface of the bottom cell, and the charge transfer solution is coated on the surface of the transparent electrode layer away from the bottom cell, that is, the perovskite cell is used as the top cell of the stacked cell.

[0032] In some embodiments, the bottom cell includes a crystalline silicon cell, and the surface of the crystalline silicon cell near the transparent electrode layer is a velvet surface. In this way, it is necessary to further conformally prepare the transparent electrode layer, the first charge transport layer, the perovskite light absorption layer, the second charge transport layer and other structures of the perovskite cell on the velvet surface. That is, the technical solution of the present invention can still effectively eliminate the residual halide salts, such as lead halide salts, on the bottom interface of the perovskite light absorption layer for the velvet stacked cell, thereby reducing the defects of the bottom interface; at the same time, it improves the sufficiency of the reaction between the perovskite inorganic layer and the perovskite organic layer, and improves the perovskite crystallization quality.

[0033] In some embodiments, there are no restrictions on the specific type and structure of the crystalline silicon cell. Those skilled in the art can flexibly select the crystalline silicon cell that can be used as the bottom cell in the stacked battery according to actual needs. For example, the crystalline silicon cell can be different types of crystalline silicon cells such as HJT crystalline silicon cells, PERC crystalline silicon cells, and TOPCon crystalline silicon cells.

[0034] S200: A charge transport solution is coated on one side of the substrate 10 and cured to obtain a first charge transport layer 21, wherein the charge transport solution includes a first charge transport material and an organic amine salt. In this process, at least part of the organic ammonium salt is distributed on the surface of the first charge transport layer. When the first charge transport layer is a self-assembled hole transport layer, the hole transport material is anchored on one side of the substrate, and the organic ammonium salt is distributed on the surface of the self-assembled hole transport layer, which can more fully react with residual lead halide and other halide salts, and react on the surface of the first charge transport layer to form a seed layer, thereby better improving the growth quality of perovskite grains.

[0035] According to some embodiments of the present invention, the organic amine salt includes at least one of formamidine hydroiodide, formamidine hydrobromide, formamidine hydrochloride, methylamine hydroiodide, methylamine hydrobromide, methylamine hydrochloride, phenylethylamine hydroiodide, phenylethylamine hydrobromide, phenylethylamine hydrochloride, ethylenediamine hydroiodide, ethylenediamine hydrobromide, ethylenediamine hydrochloride, propylenediamine hydroiodide, propylenediamine hydrobromide, propylenediamine hydrochloride, butylenediamine hydroiodide, butylenediamine hydrobromide, butylenediamine hydrochloride, oleylamine hydroiodide, oleylamine hydrobromide, oleylamine hydrochloride, 2-thiopheneethylamine hydroiodide, 2-thiopheneethylamine hydrobromide or 2-thiopheneethylamine hydrochloride. The above-mentioned organic ammonium salt can not only react with lead halide to eliminate residual lead halide and other halide salts at the bottom interface of the perovskite light-absorbing layer (i.e., the surface of the perovskite light-absorbing layer close to the first charge transport layer), thereby reducing the defects of the bottom interface; at the same time, the organic ammonium salt reacts with the inorganic salt in the perovskite inorganic layer at the bottom interface to generate a perovskite material, which can be used as a seed layer to induce the subsequent perovskite inorganic layer and the perovskite organic layer to react and grow the perovskite material, thereby improving the sufficiency of the reaction of the perovskite inorganic layer and the perovskite organic layer, and improving the perovskite crystallization quality, thereby improving the photoelectric conversion efficiency of the solar cell as a whole, while improving the yield and reproducibility of the battery.

[0036] According to some embodiments of the present invention, the molar ratio of the organic ammonium salt to the first charge transport material in the charge transport solution is 0.001 to 0.1, for example, the molar ratio of the organic ammonium salt to the first charge transport material is 0.001, 0.002, 0.004, 0.005, 0.008, 0.01, 0.02, 0.03, 0.04, 0.05, 0.06, 0.07, 0.08, 0.09, 0.1, etc. The organic ammonium salt in the above proportion can effectively react with the lead halide and other halide salts remaining at the bottom interface, eliminate the unbonded lead ions remaining at the bottom interface of the perovskite light-absorbing layer, reduce the defects of the bottom interface, and grow a seed layer to induce the subsequent perovskite inorganic layer and the perovskite organic layer to react to grow the perovskite material, thereby improving the sufficiency of the reaction between the perovskite inorganic layer and the perovskite organic layer and improving the perovskite crystallization quality; if the dosage ratio of the organic ammonium salt is too low, the improvement effect is relatively unobvious; if the dosage ratio of the organic ammonium salt is too high, it may affect the adsorption and deposition of the hole transport material, and there will be excess organic ammonium salt remaining, which will affect the growth of the perovskite grains, relatively reduce the crystallization quality, and is not conducive to the improvement of the performance of solar cells.

[0037] According to some embodiments of the present invention, the total molar concentration of the organic ammonium salt and the first charge transport material in the charge transport solution is 0.05 to 1 mmol / mL, for example, 0.05 mmol / mL, 0.06 mmol / mL, 0.07 mmol / mL, 0.08 mmol / mL, 0.09 mmol / mL, 0.1 mmol / mL, 0.2 mmol / mL, 0.3 mmol / mL, 0.4 mmol / mL, 0.5 mmol / mL, 0.6 mmol / mL, 0.7 mmol / mL, 0.8 mmol / mL, 0.9 mmol / mL, 1 mmol / mL, and the like.

[0038] According to some embodiments of the invention, the first charge transport layer may be a hole transport layer, and thus the second charge transport layer subsequently formed is an electron transport layer; according to some embodiments of the invention, the first charge transport layer is an electron transport layer, and thus the second charge transport layer subsequently formed is a hole transport layer.

[0039] According to some embodiments of the present invention, the first charge transport layer is a self-assembled hole transport layer. In some embodiments, the hole transport material includes [4-(3,6-dimethoxy-9H-carbazole-9-yl)butyl]phosphonic acid (MeO-4PACz), (4-(3,6-dimethyl-9H-carbazole-9-yl)butyl)phosphonic acid (Me-4PACz), [4-(9H-carbazole-9-yl)butyl]phosphonic acid (4PACz), (4-(3,6-dibromo-9H-carbazole-9-yl)butyl)phosphonic acid (Br-4PACz), [2-(3,6-dimethoxy-9H-carbazole-9-yl)butyl]phosphonic acid (Br-4PACz), [2-(3,6-dimethoxy-9H-carbazole-9-yl)butyl]phosphonic acid (MeO-4PACz), [4-(3,6-dimethyl-9H-carbazole-9-yl)butyl]phosphonic acid (Me-4PACz), [4-(9H-carbazole-9-yl)butyl]phosphonic acid (4PACz), [4-(3,6-dibromo-9H-carbazole-9-yl)butyl] ... At least one of [(2-(3,6-dimethyl-9H-carbazole-9-yl)ethyl]phosphonic acid (MeO-2PACz), (2-(3,6-dimethyl-9H-carbazole-9-yl)ethyl)phosphonic acid (Me-2PACz), (2-(9H-carbazole-9-yl)ethyl)phosphonic acid (2PACz), (2-(3,6-dibromo-9H-carbazole-9-yl)ethyl)phosphonic acid (Br-2PACz), [4-(7H-dibenzocarbazole-7-yl)butyl]phosphonic acid (4PADCB). The self-assembled hole transport material is anchored on the surface of the transparent electrode layer through a condensation reaction between the phosphonic acid groups in the molecule and the hydroxyl groups on the surface of the transparent electrode layer. Moreover, the technical solution of the present invention has a better improvement effect on the solar cell of the self-assembled hole transport layer.

[0040] In some other embodiments of the present invention, the hole transport layer may also be a non-self-assembled hole transport layer, and its material may include nickel oxide (NiO x, 1≤x≤2), cuprous iodide (CuI), cuprous oxide (Cu2O), cuprous thiocyanate (CuSCN), 2,2',7,7'-tetrakis[N,N-di(4-methoxyphenyl)amino]-9,9'-spirobifluorene (Spiro-OMeTAD), 2,2',7,7'-tetrakis(di-p-tolylamino)spiro-9,9'-bifluorene (Spiro-TTB), poly[bis(4-phenyl)(2,4,6-trimethylphenyl)amine] (PTAA), and [4-(3,6-dimethoxy-9H-carbazole-9-yl)butyl]phosphonic acid (MeO-4PACz), (4-(3,6-dimethyl-9H-carbazole-9-yl)butyl]phosphonic acid (MeO-4PACz), )butyl)phosphonic acid (Me-4PACz), [4-(9H-carbazole-9-yl)butyl]phosphonic acid (4PACz), (4-(3,6-dibromo-9H-carbazole-9-yl)butyl)phosphonic acid (Br-4PACz), [2-(3,6-dimethoxy-9H-carbazole-9-yl)ethyl]phosphonic acid (MeO-2PACz), (2-(3,6-dimethyl-9H-carbazole-9-yl)ethyl)phosphonic acid (Me-2PACz), (2-(9H-carbazole-9-yl)ethyl)phosphonic acid (2PACz), (2-(3,6-dibromo-9H-carbazole-9-yl)ethyl)phosphonic acid (Br-2PACz), etc.

[0041] According to other embodiments of the present invention, when the first charge transport layer is an electron transport layer, its electron transport material includes but is not limited to tin oxide, fullerene and its derivatives, imide compounds, quinone compounds, etc. Exemplarily, the imide compounds include at least one of phthalimide, succinimide, N-bromosuccinimide, glutarimide or maleimide; Exemplarily, the quinone compounds include at least one of benzoquinone, naphthoquinone, phenanthrenequinone or anthraquinone; Exemplarily, fullerene and its derivatives include fullerene C 60 , Fullerene C 70 、PCBM([6,6]-phenyl-C 61 -methyl butyrate), [6,6]-phenyl C 71 Methyl butyrate (PC 71 BM).

[0042] According to some embodiments of the present invention, the method of coating the charge transport solution includes one of spin coating, blade coating, slit coating, inkjet printing, and ultrasonic spraying. The above method can evenly coat the charge transport solution, has a mature process, and is convenient for industrial mass production.

[0043] According to some embodiments of the present invention, the charge transfer solution further includes a solvent, and the solvent may be at least one of ethanol, isopropanol, N,N-dimethylformamide, and dimethyl sulfoxide.

[0044] According to some embodiments of the present invention, after applying the charge transport solution, the first charge transport layer can be cured by thermal annealing. During the thermal annealing process, the solvent evaporates, the organic ammonium salt is retained on the surface of the first charge transport layer and forms a film, and the self-assembled hole transport material is rearranged and anchored during the thermal annealing process. In some embodiments, the thermal annealing temperature can be 100-120°C and the time can be 1-10min.

[0045] S300: forming a perovskite pre-layer 3 on a side of the first charge transport layer 21 away from the substrate, wherein the perovskite pre-layer includes an inorganic salt and an organic salt, wherein the inorganic salt includes a halide salt such as lead halide.

[0046] According to some embodiments of the present invention, the perovskite inorganic salt includes a plurality of different inorganic salts. In some embodiments, the material of the perovskite inorganic salt includes at least one of PbI2, PbBr2 or PbCl2, and at least one of CsI, CsBr or CsCl.

[0047] According to some embodiments of the present invention, the perovskite organic salt includes at least one of formamidine hydroiodide (FAI), formamidine hydrobromide (FABr), formamidine hydrochloride (FACl), methylammonium iodide (MAI), methylammonium bromide (MABr) or methylammonium chloride (MACl). The organic salt reacts with the above-mentioned perovskite inorganic salt under the induction of the seed layer to grow perovskite grains, improve the perovskite crystal quality, and also improve the reaction efficiency of the perovskite inorganic salt and the organic salt, thereby improving the photoelectric conversion efficiency of the solar cell as a whole, while improving the yield of the battery.

[0048] According to an embodiment of the present invention, the perovskite prefabricated layer can be prepared by a one-step co-evaporation method or a two-step method. Specifically:

[0049] According to some embodiments of the present invention, Figure 2 As shown, the method for preparing the perovskite pre-layer includes: using a co-evaporation method to evaporate an inorganic salt and an organic salt on the side of the first charge transport layer 21 away from the substrate 10, that is, to obtain a perovskite pre-layer 3. In some embodiments, during the preparation process, multi-source evaporation deposition is used to form the perovskite pre-layer 3, and a variety of different inorganic salts and different organic salts can be evaporated through different evaporation sources respectively. For example, when the inorganic salt includes lead iodide, lead bromide, and cesium bromide, and the organic salt includes FAI, the above four raw materials can be evaporated through four evaporation sources at the same time according to their respective evaporation rates to obtain a perovskite pre-layer mixed with organic salts and inorganic salts.

[0050] According to some embodiments of the present invention, there are no special requirements for the evaporation rates of different inorganic salts and organic salts. Those skilled in the art can flexibly choose according to the actual situation such as the composition of the perovskite light-absorbing layer and current technical means, and no restrictions are imposed herein.

[0051] According to other embodiments of the present invention, Figure 3 The method for preparing the perovskite prefabricated layer includes: firstly depositing an inorganic salt on the side of the first charge transport layer 21 away from the substrate 10 by evaporation to form a perovskite inorganic layer 31; and then depositing an organic salt on the surface of the perovskite inorganic layer 31 away from the substrate 10 by evaporation to form a perovskite organic layer 32, or coating an organic salt solution on the surface of the perovskite inorganic layer away from the substrate by a solution method to form a perovskite organic layer 32.

[0052] In some embodiments, during the preparation process, multi-source evaporation deposition can be used to form the perovskite inorganic layer, and different inorganic salts can be evaporated through different evaporation sources. For example, two evaporation sources can be included to evaporate two different inorganic salts respectively; or three evaporation sources can be included to evaporate three different inorganic salts respectively, such as lead iodide, lead bromide and cesium bromide respectively. In this way, a variety of different perovskite inorganic salts are co-evaporated, which is conducive to the uniform distribution of the perovskite inorganic salts, which can help promote the reaction between the perovskite inorganic salts, and thus can effectively improve the subsequent reaction efficiency of the perovskite inorganic salt and the perovskite organic salt.

[0053] Among them, in some embodiments, there are no special requirements for the evaporation rates of different inorganic salts. Those skilled in the art can flexibly choose according to the actual situation such as the composition of the perovskite light-absorbing layer and current technical means, and no restrictions are imposed here.

[0054] In some embodiments, the thickness of the perovskite organic layer is 100-400 nm, such as 100 nm, 110 nm, 120 nm, 130 nm, 140 nm, 150 nm, 160 nm, 170 nm, 180 nm, 190 nm, 200 nm, 300 nm, 400 nm, etc. This is conducive to the full reaction of the perovskite inorganic salt and the organic salt, and a perovskite light-absorbing layer of suitable thickness is obtained.

[0055] In some embodiments, when the perovskite organic layer is formed by evaporation deposition, the evaporation rate of the perovskite organic layer can be

[0056] In some embodiments, when the perovskite organic layer is formed by a solution method, the perovskite organic layer can be prepared by spin coating, doctor blading, slit coating, inkjet printing, ultrasonic spraying, or the like.

[0057] S500 : performing annealing treatment on the perovskite inorganic layer 31 and the perovskite organic layer 32 to obtain the perovskite light absorbing layer 30 .

[0058] According to some embodiments of the present invention, the annealing treatment conditions may be heating at 100-200°C (e.g., the heat treatment temperature is 100°C, 110°C, 120°C, 130°C, 140°C, 150°C, 160°C, 170°C, 180°C, 190°C, 200°C, etc.) for 10-60min (e.g., 10min, 20min, 30min, 35min, 40min, 45min, 50min, 55min, 60min, etc.) in an air atmosphere or an atmosphere with a humidity of 20%-60%. Under the above conditions, the reaction of the inorganic perovskite salt and the organic perovskite salt can be effectively promoted to obtain a perovskite light-absorbing layer with good performance.

[0059] According to some embodiments of the present invention, the thickness of the obtained perovskite light absorbing layer may be 250 nm to 700 nm.

[0060] According to some embodiments of the present invention, referring to Figure 3 , the method for preparing a solar cell further comprises:

[0061] S600 : forming a second charge transport layer 22 on a side of the perovskite light absorbing layer 30 away from the substrate 10 .

[0062] According to some embodiments of the present invention, the above-mentioned first charge transport layer is a hole transport layer, and the second charge transport layer is an electron transport layer; according to some embodiments of the present invention, the above-mentioned first charge transport layer is an electron transport layer, and the second charge transport layer is a hole transport layer.

[0063] In some embodiments, the second charge transport layer can be prepared by magnetron sputtering, atomic deposition, spin coating, etc.

[0064] S700 : forming a buffer layer 40 on a side of the second charge transport layer 22 away from the substrate 10 .

[0065] According to some embodiments of the present invention, the material of the buffer layer is at least one of bathocuproine (BCP) or tin dioxide (SnO2).

[0066] According to some embodiments of the present invention, the buffer layer can be prepared by coating, spin coating, atomic layer deposition or other methods.

[0067] S800 : forming an electrode 50 on a side of the buffer layer 40 away from the substrate 10 .

[0068] According to some embodiments of the present invention, the electrode may be a metal electrode, such as a silver electrode or a copper electrode.

[0069] According to some embodiments of the present invention, patterned metal silver grid lines or copper grid lines, ie, electrodes, may be prepared by thermal evaporation or screen printing.

[0070] According to an embodiment of the present invention, in the above-mentioned preparation method, an organic ammonium salt is added to the charge transport solution, so that the organic ammonium salt is distributed on the surface of the first charge transport layer formed away from the substrate (or the interface between the first charge transport layer and the perovskite inorganic layer), and the organic ammonium salt can react with the lead halide in the subsequent perovskite inorganic layer to eliminate the residual lead ions at the bottom interface of the perovskite light-absorbing layer (that is, the surface of the perovskite light-absorbing layer close to the first charge transport layer), thereby reducing the defects of the bottom interface; at the same time, the organic ammonium salt reacts with the inorganic salt in the perovskite inorganic layer at the bottom interface to generate a perovskite material, and the perovskite material can be used as a seed layer to induce the subsequent perovskite inorganic layer and the perovskite organic layer to react and grow the perovskite material, thereby improving the sufficiency of the reaction of the perovskite inorganic layer and the perovskite organic layer, and improving the perovskite crystallization quality, thereby improving the photoelectric conversion efficiency of the solar cell as a whole, while improving the yield and reproducibility of the battery.

[0071] In another aspect of the present invention, the present invention provides a solar cell, according to an embodiment of the present invention. The solar cell is prepared by the method described above. Thus, the solar cell has a better energy conversion efficiency. Those skilled in the art can understand that the solar cell has all the features and advantages of the method for preparing a solar cell described above, and no further elaboration is given here.

[0072] In another aspect of the present invention, the present invention provides an electric device. According to an embodiment of the present invention, the electric device includes the solar cell described above. Thus, the electric device has good power usage performance. Those skilled in the art can understand that the electric device has all the features and advantages of the solar cell described above, and no further elaboration is given here.

[0073] According to some embodiments of the present application, electrical devices may include mobile devices (such as mobile phones, laptops, etc.), electric vehicles (such as pure electric vehicles, hybrid electric vehicles, plug-in hybrid electric vehicles, electric bicycles, electric scooters, electric golf carts, electric trucks, etc.), electric trains, ships and satellites, energy storage systems, etc., but are not limited thereto.

[0074] In another aspect of the present invention, the present invention provides a power generation device. According to an embodiment of the present invention, the power generation device includes the solar cell described above. Thus, the power generation device has good power generation efficiency. Those skilled in the art can understand that the power generation device has all the features and advantages of the solar cell described above, and no further elaboration is given here.

[0075] In some embodiments, the power generation device can be used in ground power stations, aviation, construction, wearable power generation devices and other fields.

[0076] Example

[0077] Example 1

[0078] (1) providing an HJT crystalline silicon cell having a textured surface, wherein the structure is Ag / TCO / α-Si:H(p+) / α-Si:H(i) / c-Si(n) / α-Si:H(i) / α-Si:H(n+), wherein α-Si:H(n+) is the provided substrate texture;

[0079] (2) In the suede α-Si:H(n + ) surface conformally preparing an ITO transparent electrode layer;

[0080] (3) coating a hole transport solution of a self-assembled hole transport material Me-4PACz and formamidine hydroiodide (FAI) on the surface of the ITO transparent electrode layer by a slit coating method, wherein the concentration of Me-4PACz is 0.3 mmol / mL and the concentration of FAI is 0.0003 mmol / mL, and heating at 100° C. for 5 min to obtain a self-assembled hole transport layer, and the surface has an organic ammonium salt film;

[0081] (4) PbI2, CsBr, PbBr2 and FAI are co-evaporated on the surface of the self-assembled hole transport layer to form a perovskite pre-layer, wherein the evaporation rate of PbI2 is The evaporation rate of CsBr is The evaporation rate of PbBr2 is FAI evaporation rate

[0082] (5) The perovskite prefabricated layer obtained in step (4) is annealed at a humidity of 50%, an annealing temperature of 170° C., and an annealing time of 40 min to obtain a perovskite prefabricated layer having a component of Cs 0.2 FA 0.8 Pb(I 0.8 Br 0.2 )3 perovskite light absorbing layer, band gap is about 1.68eV, thickness is 500nm;

[0083] (6) Using evaporation method, a 20 nm thick electron transport layer C is deposited on the surface of the perovskite light absorption layer. 60 , a 15 nm thick buffer layer SnO2 is deposited on the surface of the electron transport layer by atomic layer deposition;

[0084] (7) Patterned metal silver grid lines are prepared using screen printing to complete the preparation of perovskite / crystalline silicon stacked solar cells.

[0085] Example 2

[0086] The steps for preparing the perovskite / crystalline silicon tandem solar cell are basically the same as those in Example 1, except that in step (3), the concentration of FAI is 0.0015 mmol / mL.

[0087] Example 3

[0088] The steps for preparing the perovskite / crystalline silicon tandem solar cell are basically the same as those in Example 1, except that in step (3), the concentration of FAI is 0.003 mmol / mL.

[0089] Example 4

[0090] The steps for preparing the perovskite / crystalline silicon tandem solar cell are basically the same as those in Example 1, except that in step (3), the concentration of FAI is 0.015 mmol / mL.

[0091] Example 5

[0092] The steps for preparing the perovskite / crystalline silicon tandem solar cell are basically the same as those in Example 1, except that in step (3), the concentration of FAI is 0.03 mmol / mL.

[0093] Example 6

[0094] The steps for preparing the perovskite / crystalline silicon tandem solar cell are basically the same as those in Example 1, except that in step (3), the concentration of FAI is 0.045 mmol / mL.

[0095] Example 7

[0096] The steps for preparing the perovskite / crystalline silicon stacked solar cell are basically the same as those in Example 3, except that in step (3), the organic ammonium salt used is methylamine hydroiodide.

[0097] Example 8

[0098] The steps for preparing the perovskite / crystalline silicon tandem solar cell are basically the same as those in Example 3, except that in step (3), the organic ammonium salt used is 2-thiopheneethylamine hydroiodide.

[0099] Comparative Example 1

[0100] The steps for preparing the perovskite / crystalline silicon tandem solar cell are basically the same as those in Example 1, except that in step (3), no organic ammonium salt is added to the hole transport solution.

[0101] The data of parameter changes in the above-mentioned embodiments 1 to 6 and comparative example 1 are shown in Table 1. The solar cells obtained in the above-mentioned embodiments 1 to 6 and comparative example 1 are subjected to performance tests, and the test data can be seen in Table 1 below. The test method is: the solar cell is placed under a standard sunlight intensity of AM1.5G, a source meter is used to electrically connect the battery, and a 10mV step voltage is used to scan in the range of 2V to -0.5V, and the current output by the solar cell at each voltage point is recorded, so as to obtain the power conversion efficiency PCE and the open circuit voltage V of the battery. OC , short circuit current density J SC And fill factor FF. And each optoelectronic parameter satisfies the formula: PCE=V OC ×J SC ×FF.

[0102] Table 1

[0103]

[0104] It can be seen from the above data that compared with Comparative Example 1, adding an appropriate amount of organic ammonium salt to the hole transport material solution can effectively improve the conversion efficiency of the solar cell; as the content of organic ammonium salt FAI gradually increases, the conversion efficiency of the solar cell gradually increases, but when the content of organic ammonium salt FAI is too much, such as Example 6, the conversion efficiency of the solar cell decreases. It can be seen that adding an appropriate amount of organic ammonium salt to the hole transport material solution can effectively improve the conversion efficiency of the solar cell, but too much organic ammonium salt has a certain negative effect on the conversion efficiency of the solar cell.

[0105] The terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include one or more of the features. In the description of this application, the meaning of "plurality" is two or more, unless otherwise clearly and specifically defined.

[0106] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine the different embodiments or examples described in this specification and the features of the different embodiments or examples, unless they are contradictory.

[0107] Although the embodiments of the present invention have been shown and described above, it is to be understood that the above embodiments are exemplary and are not to be construed as limitations of the present invention. A person skilled in the art may change, modify, replace and vary the above embodiments within the scope of the present invention.

Claims

1. A method for preparing a solar cell, characterized in that: include: providing a substrate; Applying a charge transport solution on one side of the substrate and curing the solution to obtain a first charge transport layer, wherein the charge transport solution includes a first charge transport material and an organic amine salt; forming a perovskite pre-layer on a side of the first charge transport layer away from the substrate, wherein the perovskite pre-layer comprises an inorganic salt and an organic salt, and the inorganic salt comprises a halide salt; The perovskite prefabricated layer is annealed to obtain a perovskite light absorbing layer.

2. The method according to claim 1, characterized in that The organic amine salt includes at least one of formamidine hydroiodide, formamidine hydrobromide, formamidine hydrochloride, methylamine hydroiodide, methylamine hydrobromide, methylamine hydrochloride, phenylethylamine hydroiodide, phenylethylamine hydrobromide, phenylethylamine hydrochloride, ethylenediamine hydroiodide, ethylenediamine hydrobromide, ethylenediamine hydrochloride, propylenediamine hydroiodide, propylenediamine hydrobromide, propylenediamine hydrochloride, butylene diamine hydroiodide, butylene diamine hydrobromide, butylene diamine hydrochloride, oleylamine hydroiodide, oleylamine hydrobromide, oleylamine hydrochloride, 2-thiopheneethylamine hydroiodide, 2-thiopheneethylamine hydrobromide or 2-thiopheneethylamine hydrochloride.

3. The method according to claim 1 or 2, characterized in that: The molar ratio of the organic ammonium salt to the first charge transport material in the charge transport solution is 0.001 to 0.

1.

4. The method according to claim 3, characterized in that The total molar concentration of the organic ammonium salt and the first charge transport material in the charge transport solution is 0.05 to 1 mmol / mL.

5. The method according to claim 1 or 2, characterized in that: The first charge transport layer is a self-assembled hole transport layer.

6. The method according to claim 5, characterized in that The first charge transport material includes at least one of [4-(3,6-dimethoxy-9H-carbazole-9-yl)butyl]phosphonic acid, (4-(3,6-dimethyl-9H-carbazole-9-yl)butyl)phosphonic acid, [4-(9H-carbazole-9-yl)butyl]phosphonic acid, (4-(3,6-dibromo-9H-carbazole-9-yl)butyl)phosphonic acid, [2-(3,6-dimethoxy-9H-carbazole-9-yl)ethyl]phosphonic acid, (2-(3,6-dimethyl-9H-carbazole-9-yl)ethyl)phosphonic acid, (2-(9H-carbazole-9-yl)ethyl)phosphonic acid, (2-(3,6-dibromo-9H-carbazole-9-yl)ethyl)phosphonic acid, and [4-(7H-dibenzocarbazole-7-yl)butyl]phosphonic acid.

7. The method according to claim 1 or 2, characterized in that: The method of coating the charge transport solution includes one of spin coating, blade coating, slit coating, inkjet printing, and ultrasonic spraying.

8. The method according to claim 1 or 2, characterized in that: The method for preparing the perovskite prefabricated layer comprises: using a co-evaporation method to evaporate the inorganic salt and the organic salt on a side of the first charge transport layer away from the substrate, Alternatively, the method for preparing the perovskite prefabricated layer includes: firstly depositing the inorganic salt on the side of the first charge transport layer away from the substrate by evaporation to form the perovskite inorganic layer; and then depositing the organic salt on the surface of the perovskite inorganic layer away from the substrate by evaporation to form the perovskite organic layer, or coating an organic salt solution on the surface of the perovskite inorganic layer away from the substrate by a solution method to form the perovskite organic layer.

9. The method according to claim 1 or 2, characterized in that: The inorganic salt includes at least one of PbI2, PbBr2 or PbCl2, and at least one of CsI, CsBr or CsCl; The organic salt includes at least one of formamidine hydroiodide, formamidine hydrobromide, formamidine hydrochloride, methylammonium iodide, methylammonium bromide or methylammonium chloride.

10. The method according to claim 1 or 2, characterized in that: The substrate is a transparent electrode layer; Alternatively, the substrate includes a bottom cell and the transparent electrode layer located on a surface of the bottom cell, and the charge transport solution is coated on a surface of the transparent electrode layer away from the bottom cell.

11. The method according to claim 10, characterized in that The bottom cell comprises a crystalline silicon cell, and a surface of the crystalline silicon cell close to the transparent electrode layer is a velvet surface.

12. The method according to claim 1 or 2, characterized in that: Also includes; forming a second charge transport layer on a side of the perovskite light absorbing layer away from the substrate; An electrode is formed on a side of the second charge transport layer away from the substrate.

13. A solar cell, characterized in that: It is prepared by the method according to any one of claims 1 to 12.

14. An electrical device, characterized in that: The electrical device comprises the solar cell according to claim 13.

15. A power generation device, characterized in that: The power generation device comprises the solar cell according to claim 13.

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