Laminated cell and preparation method thereof

Abstract

The invention provides a laminated cell and a preparation method thereof. The laminated cell comprises at least one perovskite sub-cell, the perovskite sub-cell comprises a perovskite absorption layer and a passivation layer arranged on the perovskite absorption layer, and the passivation layer contains a compound shown in the formula A. According to the invention, the compound in the formula A is introduced into the passivation layer of the laminated cell as a passivation material, so that the energy band matching between the perovskite thin film and other functional layers such as a buffer layer can be regulated and controlled, and the device performance is optimized. ; wherein R1 and R2 are respectively and independently selected from O, NH, CH2 or S; wherein X is halogen; and n is 0, 1 or 2.

Description

Technical Field

[0001] This invention belongs to the field of solar cells, and specifically relates to a tandem solar cell and its preparation method. Background Technology

[0002] The theoretical efficiency limit (SQ limit) of traditional monocrystalline silicon solar cells is approximately 33.7%, while the efficiency of commercially available crystalline silicon cells has reached 24%–26%, posing a significant challenge to further improving efficiency. Therefore, tandem solar cells have become a key technology for overcoming this bottleneck.

[0003] Perovskite / c-Si tandem solar cells combine the wide bandgap and high absorption coefficient of perovskite materials with the mature industrial advantages of crystalline silicon cells, significantly improving light absorption and carrier collection efficiency. However, in tandem structures, interfacial recombination and surface defects are among the main factors limiting cell performance. In both crystalline silicon and perovskite materials, surface defects generate nonradiative recombination centers, reducing carrier lifetime and causing open-circuit voltage (Voc) loss. Furthermore, in humid environments, surface defects become channels for ion migration, accelerating material decomposition and device performance degradation. Therefore, surface passivation has become a key technology for improving cell performance.

[0004] However, compared to single-junction cells, the passivation of perovskite-crystalline silicon tandem cells is more complex: lattice mismatch between the two materials leads to a high defect state density at the interface; different process windows (such as temperature) pose greater challenges to heterojunction passivation. Summary of the Invention

[0005] To overcome the problems existing in the prior art, this invention provides a tandem solar cell and its fabrication method. By introducing compound A as a passivation material into the passivation layer of the tandem solar cell, this invention can regulate the bandgap matching between the perovskite thin film and other functional layers, such as buffer layers, thereby optimizing device performance, especially photoelectric performance.

[0006] Specifically, a first aspect of the present invention provides a stacked battery, the stacked battery comprising at least one perovskite sub-cell, the perovskite sub-cell comprising a perovskite absorber layer and a passivation layer disposed on the perovskite absorber layer, the passivation layer comprising a compound of formula A: ; Among them, R1 and R2 are each independently selected from O, NH, CH2 or S; Where X is a halogen; n is 0, 1 or 2.

[0007] In one or more implementations, R1 and R2 may be the same or different.

[0008] In one or more embodiments, X is selected from one or more of Cl, Br, and I.

[0009] In one or more embodiments, the number of X in formula A is 1-8, preferably 2-6.

[0010] In one or more embodiments, the compound of formula A has the structure of formula A-1: ; Where X is Cl and / or Br; n is 0, 1 or 2; the number of X is 1-8.

[0011] In one or more embodiments, compound A has the structure shown in formula A-2: ; Wherein, X is selected from Cl and / or Br.

[0012] In one or more embodiments, the passivation layer further comprises an organic ammonium salt; the mass ratio of compound A to the organic ammonium salt is 1:(1-50).

[0013] In one or more embodiments, the organic ammonium salt is selected from organic ammonium iodide salts and / or organic ammonium hydrochloride salts.

[0014] In one or more embodiments, the organic ammonium salt is selected from one or more of propylenediamine iodine, phenylethylamine iodide, 4-trifluoromethyl-aniline hydrochloride, 2-thiophene ethylamine hydrochloride, ethylamine hydrochloride, and n-butylamine hydrochloride.

[0015] In one or more embodiments, the perovskite sub-cell includes a hole transport layer, a perovskite absorber layer, the passivation layer, an electron transport layer, a buffer layer, a transparent electrode, and a metal electrode arranged sequentially.

[0016] In one or more embodiments, the stacked cell is a stacked perovskite-crystalline silicon cell.

[0017] In one or more embodiments, the stacked solar cell includes a crystalline silicon base cell and a perovskite sub-cell, wherein the perovskite sub-cell includes a hole transport layer, a perovskite absorption layer, a passivation layer, an electron transport layer, a buffer layer, a transparent electrode, and a metal electrode arranged sequentially; wherein the hole transport layer is disposed on the side close to the crystalline silicon base cell.

[0018] A second aspect of the present invention provides a method for preparing a tandem battery as described in any embodiment herein, the method comprising: depositing a passivation material containing a compound of formula A on the surface of the perovskite absorber layer of the perovskite sub-cell, and annealing to obtain the passivation layer.

[0019] In one or more embodiments, the deposition is carried out by evaporation.

[0020] In one or more embodiments, the annealing conditions are as follows: annealing in an inert atmosphere at a temperature of 80-120°C.

[0021] In one or more embodiments, the method includes: depositing a passivation material containing a compound of formula A and an organic ammonium salt onto the surface of a perovskite absorber layer using a co-evaporation method, followed by annealing to obtain the passivation layer.

[0022] In one or more embodiments, the method further includes: providing a crystalline silicon bottom cell before preparing the passivation layer, and sequentially depositing a hole transport layer and a perovskite light-absorbing layer on the surface of the crystalline silicon bottom cell; and after preparing the passivation layer, sequentially depositing an electron transport layer, a transparent electrode, and a metal on the surface of the passivation layer.

[0023] A third aspect of the present invention provides the use of the compound of formula A in the preparation of tandem solar cells with improved photoelectric performance.

[0024] In one or more embodiments, the compound of formula A and the organic ammonium salt are used in the preparation of tandem solar cells with improved photoelectric performance.

[0025] In one or more embodiments, the use of the compound of formula A and the optional organic ammonium salt in the preparation of a passivation layer, or in the preparation of a perovskite thin film containing the passivation layer. Detailed Implementation

[0026] To enable those skilled in the art to understand the features and effects of this invention, the terms and expressions used herein are explained and defined in general terms below. Unless otherwise specified, all technical and scientific terms used herein have the common meaning understood by those skilled in the art regarding this invention, and in case of conflict, the definitions herein shall prevail.

[0027] The theories or mechanisms described and disclosed herein, whether right or wrong, should not in any way limit the scope of the invention, that is, the contents of the invention can be implemented without being limited by any particular theory or mechanism.

[0028] In this document, the terms “contains,” “includes,” “containing,” and similar terms encompass the meanings of “basically composed of” and “composed of.” For example, when this document discloses “A contains B and C,” “A is basically composed of B and C” and “A is composed of B and C” should be considered as having been disclosed in this document.

[0029] In this document, all features defined in the form of numerical ranges or percentage ranges, such as numerical values, quantities, contents, and concentrations, are for the sake of brevity and convenience only. Accordingly, descriptions of numerical ranges or percentage ranges should be considered as covering and specifically disclosing all possible sub-ranges and individual numerical values ​​(including integers and fractions) within those ranges.

[0030] Unless otherwise specified, percentages refer to mass percentages and proportions refer to mass ratios in this article.

[0031] In this document, when describing embodiments or examples, it should be understood that it is not intended to limit the invention to those embodiments or examples. Rather, all alternatives, modifications, and equivalents of the methods and materials described herein are covered within the scope defined by the claims.

[0032] For the sake of brevity, not all possible combinations of the technical features in each implementation scheme or embodiment are described herein. Therefore, as long as there is no contradiction in the combination of these technical features, the technical features in each implementation scheme or embodiment can be combined arbitrarily, and all possible combinations should be considered within the scope of this specification.

[0033] This invention introduces compound A as a passivation material into the passivation layer of a tandem battery. Compared with compound A without halogen substitution, it can regulate the bandgap matching between the perovskite film and other functional layers such as buffer layers, thereby optimizing device performance, especially photoelectric performance.

[0034] passivation layer

[0035] This invention provides a passivation layer disposed on the surface of a perovskite absorber layer (perovskite thin film), the passivation layer containing a compound of formula A: ; In this context, R1 and R2 are each independently selected from O, NH, CH2, or S; X is a halogen; and n is 0, 1, or 2.

[0036] In some implementations, R1 and R2 may be the same or different.

[0037] In some embodiments, X is selected from one or more of Cl, Br and I, preferably Cl and / or Br.

[0038] In some implementations, the number of X in formula A is 1-8, preferably 2-6.

[0039] In some embodiments, the compound of formula A has the structure of formula A-1: ; Where X is a halogen, preferably Cl and / or Br; n is 0, 1 or 2; and the number of X is 1-8.

[0040] In some embodiments, compound A is perylene chloride tetracarboxylic anhydride or perylene bromide tetracarboxylic anhydride.

[0041] In some specific embodiments, compound A has the structure shown in formula A-2: ; Where X is selected from Cl and / or Br.

[0042] In some embodiments, the passivation layer further contains passivating agents conventional in the art, such as organic ammonium salts. Suitable organic ammonium salts for this invention include, but are not limited to, organic ammonium iodides or organic ammonium hydrochlorides. In some embodiments, the organic ammonium iodide is an organic ammonium iodide containing 1-10 carbon atoms, preferably propylenediamine iodide (PDADI) and / or phenylethylamine iodide (PEAI). In some embodiments, the organic ammonium hydrochloride is an organic ammonium hydrochloride containing 1-10 carbon atoms, preferably selected from one or more of 4-trifluoromethyl-aniline hydrochloride (CF3-PACl), 2-thiopheneethylamine hydrochloride (TEACl), ethylamine hydrochloride (EACl), and n-butylamine hydrochloride (BACl). The inventors have discovered that by combining the compound of formula A with an organic ammonium salt, the photoelectric performance of the tandem solar cell can be further improved.

[0043] In some embodiments, the mass ratio of compound A to organoammonium salt is 1:(1-50), for example 1:(1-30) or 1:(2-10).

[0044] Methods for preparing passivation layers

[0045] The passivation layer of the present invention can be prepared by deposition.

[0046] In some embodiments, the present invention provides a method for preparing a passivation layer, comprising depositing a passivation material containing a compound of formula A on the surface of a perovskite absorber layer, and annealing to obtain the passivation layer.

[0047] In some embodiments, the deposition method can be wet film deposition or evaporation. Specific wet film deposition methods include, but are not limited to, spin coating, blade coating, etc. In some preferred embodiments, the deposition method is evaporation.

[0048] In some preferred embodiments, the present invention provides a method for preparing a passivation layer, comprising depositing a passivation material containing a compound of formula A onto the surface of a perovskite absorber layer by evaporation, followed by annealing to obtain the passivation layer. The evaporation rate can be 0.01-0.1 Å / s, for example 0.03-0.07 Å / s.

[0049] In some embodiments, the passivating material containing compound A further contains an organic ammonium salt. This organic ammonium salt can be as described above. The passivating material containing compound A and the organic ammonium salt can be deposited on the surface of the perovskite absorber layer using a co-evaporation method, followed by annealing to obtain the passivation layer. In some specific embodiments, the passivation layer can be obtained by placing compound A and the organic ammonium salt separately in two evaporation containers, such as crucibles, adjusting the corresponding evaporation rates of their respective materials, and then co-evaporating compound A and the organic ammonium salt onto the surface of the perovskite absorber layer, followed by annealing. The ratio of the evaporation rates of compound A and the organic ammonium salt can be the mass ratio of compound A and the organic ammonium salt, specifically 1:(1-50), for example 1:(1-30) or 1:(2-10). In some embodiments, the evaporation rate of compound A is 0.01-0.1 Å / s, for example 0.03-0.07 Å / s; and the evaporation rate of PDADI is 0.05-0.5 Å / s, for example 0.05-0.2 Å / s.

[0050] After deposition, a film thickness of 0.5-5 nm, such as 1-3 nm, is obtained. Annealing is then performed. The purpose of annealing is twofold: to remove the solvent and to allow the film to crystallize and grow under thermal drive. Annealing conditions can include annealing in an inert atmosphere such as N2, at a temperature of 80-120°C. An exemplary annealing time can be 5-20 minutes. The "expansion" of the film after annealing is negligible; therefore, the thickness of the annealed film is almost the same as the thickness after deposition.

[0051] Perovskite absorber layer

[0052] In this invention, the type of perovskite absorber layer is not particularly limited, and any perovskite absorber layer conventional in the art can be used. In some embodiments, the chemical formula of the perovskite material in the perovskite absorber layer can be ABX3, wherein A is a monovalent cation, which may include, but is not limited to, one or a mixture of several monovalent cations selected from cesium (Cs), rubidium (Rb), methylamino (CH3NH3), and formamidinyl (CH2(NH2)2); B is a divalent cation, which may include, but is not limited to, one or a mixture of several divalent cations selected from lead (Pb), copper (Cu), zinc (Zn), gallium (Ga), tin (Sn), and calcium (Ca); and X is a monovalent anion, which may include, but is not limited to, one or a mixture of several monovalent anions selected from iodine (I), bromine (Br), chloride (Cl), fluorine (F), and thiocyanate (SCN). In some embodiments, A is Cs, MA (methylamino), and FA (formamidinyl), B is Pb, and C is Br and I. In some specific implementations, the perovskite material is a mixture of CsI, MABr, FAI, PbBr2 and PbI2.

[0053] The perovskite absorber layer (perovskite thin film) of the present invention can be prepared using conventional methods. An exemplary method includes coating a perovskite precursor solution onto a substrate and annealing to obtain the perovskite thin film. The coating method is not particularly limited and includes, but is not limited to, one or more of spin coating, blade coating, vapor deposition, printing, spraying, spray pyrolysis, and slot coating. In some embodiments, spin coating is used to prepare the perovskite thin film. Process parameters can be adjusted according to the target thickness of the perovskite thin film. In some embodiments, the spin coating conditions are: a spin coating rate of 800-8000 r / s, such as 1000-6000 r / s, and a spin coating time of 15-50 s, such as 18-25 s. In some specific implementations, the coating process can begin with spin coating at 800-1200 r / s (e.g., 1000 r / s) for 8-12 s (e.g., 10 s); followed by spin coating at 1800-2400 r / s (e.g., 2000 r / s) for 35-45 s (e.g., 40 s); and then spin coating at 5800-6200 r / s (e.g., 6000 r / s) for 15-25 s (e.g., 20 s), with 180-220 μL (e.g., 200 μL) of anti-solvent CB (chlorobenzene) added dropwise at the 40th-50th (e.g., 45th) s to obtain a perovskite wet film. Annealing is then performed to remove the solvent. Exemplary annealing conditions include an annealing temperature of 100-150°C and an annealing time of 10-30 min. After annealing, a perovskite thin film (perovskite absorber layer) is obtained.

[0054] Stacked batteries

[0055] The present invention provides a stacked battery, which includes at least one perovskite sub-cell. The perovskite sub-cell includes a perovskite absorber layer and a perovskite passivation layer disposed on the perovskite absorber layer, wherein the perovskite passivation layer is as described above.

[0056] In this invention, the stacked battery can be a two-junction stacked battery or a stacked battery with two or more junctions. Stacked batteries with two or more junctions include, but are not limited to, three-junction stacked batteries, four-junction stacked batteries, etc.

[0057] In some embodiments, the perovskite sub-cell of the present invention includes a hole transport layer, a perovskite absorber layer, a passivation layer as described herein, an electron transport layer, a buffer layer, a transparent electrode, and a metal electrode arranged sequentially.

[0058] Materials suitable for the hole transport layer of the present invention include, but are not limited to, organic hole transport materials, inorganic hole transport materials, self-assembled monolayer (SAM) materials, etc., with SAM materials being preferred. In some embodiments, the hole transport material includes one or more of [2-(9H-carbazole-9-yl)ethyl]phosphonic acid (abbreviated as 2PACZ), (2-(3,6-dimethoxy-9H-carbazole-9-yl)ethyl)phosphonic acid (abbreviated as MeO-2PACZ), (4-(3,6-dimethyl-9H-carbazole-9-yl)butyl)phosphonic acid (abbreviated as Me-4PACZ), 2-(4-(bis(4-methoxyphenyl)amino)phenyl)-1-cyanovinylphosphonic acid (abbreviated as MPA-CPA), and (4-(2,7-dibromo-9,9-dimethylacridin-10(9H)yl)butyl)phosphonic acid (abbreviated as DMAcPA), PEDOT:PSS (poly(3,4-ethylenedioxythiophene):polystyrene sulfonate), NiOx, and CuSCN. In some embodiments, the material of the hole transport layer is selected from MeO-2PACZ.

[0059] Materials suitable for the electron transport layer of this invention include, but are not limited to, PCBM ([6,6]-phenyl-C71-isomethyl butyrate), TiO2, SnO2, ZnO2, Al2O3, C60, and ICBA (indene-C60 diadduct). In some specific embodiments, the material of the electron transport layer is selected from C60.

[0060] Materials suitable for the buffer layer of this invention include, but are not limited to, BCP (2,9-dimethyl-4,7-biphenyl-1,10-o-phenanthroline), MoOx (molybdenum oxide), and IZO. In some embodiments, the buffer layer material is SnO2.

[0061] Materials suitable for the transparent electrode of the present invention include, but are not limited to, indium tin oxide (ITO), fluorine-doped tin oxide (FTO), IZO, AZO, and IWO. In some embodiments, the transparent electrode material is IZO.

[0062] The material of the metal electrode suitable for use in this invention can be selected from one or more of silver, copper, and Au. In some embodiments, the material of the metal electrode is Ag.

[0063] In some embodiments, the present invention provides a tandem perovskite-crystalline silicon solar cell. The tandem perovskite-crystalline silicon solar cell includes a crystalline silicon base cell and one or more perovskite sub-cells.

[0064] In some embodiments, the perovskite sub-cell is as described above, wherein the hole transport layer is disposed on the side close to the crystalline silicon base cell.

[0065] In this invention, the crystalline silicon base cell applicable to this invention can be a crystalline silicon sub-cell conventionally used in the art to prepare tandem perovskite-crystalline silicon cells, including but not limited to HJT. In some embodiments, the crystalline silicon sub-cell can be a commercially available crystalline silicon sub-cell. An exemplary crystalline silicon sub-cell structure may include a metal electrode such as Ag, a transparent metal oxide layer such as ITO, a-Si:H(p+), a-Si:H(i), c-Si(n), a-Si:H(i), and a-Si:H(n+) arranged sequentially.

[0066] The present invention also provides a method for preparing the above-mentioned stacked battery, which includes the step of preparing a perovskite passivation layer on the surface of the perovskite absorber layer using the method for preparing a passivation layer described herein.

[0067] In some embodiments, the present invention provides a method for fabricating a stacked perovskite-crystalline silicon solar cell, comprising the following steps: providing a crystalline silicon base cell; and sequentially depositing a hole transport layer, a perovskite light-absorbing layer, a passivation layer as described herein, an electron transport layer, a transparent electrode, and a metal on the surface of the crystalline silicon base cell, wherein the passivation layer can be fabricated using the method for preparing a passivation layer described herein.

[0068] The fabrication of the hole transport layer is not particularly limited, and conventional methods in the art can be used, such as spin coating, blade coating, or slot coating. Process parameters can be adjusted according to the target thickness of the hole transport layer. In some embodiments, the thickness of the hole transport layer is 2-5 nm.

[0069] The fabrication of the electron transport layer is not particularly limited, and conventional methods in the art can be used, including but not limited to one or more of spin coating, spray coating, spray pyrolysis, slot coating, and evaporation. Process parameters can be adjusted according to the target thickness of the electron transport layer. In some embodiments, the thickness of the electron transport layer is 10 nm-100 nm, such as 20-40 nm.

[0070] The preparation of the buffer layer is not particularly limited, and conventional methods in the art can be used, including but not limited to one or more of spin coating, spray coating, spray pyrolysis, slot coating, and atomic layer deposition. Process parameters can be adjusted according to the target thickness of the buffer layer. In some embodiments, the thickness of the buffer layer is 10 nm-80 nm, such as 15-40 nm.

[0071] The fabrication of the transparent electrode is not particularly limited, and conventional methods for fabricating transparent conductive electrodes in the art can be used, such as magnetron sputtering or atomic layer deposition. Process parameters can be adjusted according to the target thickness of the transparent electrode. In some embodiments, the thickness of the transparent electrode is 20 nm–100 nm, such as 40–60 nm.

[0072] The fabrication of the metal electrode is not particularly limited, and conventional methods for fabricating transparent conductive electrodes in the art can be used, such as magnetron sputtering or evaporation. Process parameters can be adjusted according to the target thickness of the metal electrode. In some embodiments, the thickness of the metal electrode is 90 nm–400 nm, such as 100–250 nm.

[0073] application

[0074] This invention provides the application of the compound of formula A described in any embodiment of the present invention in the preparation of tandem solar cells with improved photoelectric performance.

[0075] In some embodiments, the present invention provides the use of the compound of formula A and the organic ammonium salt described in any embodiment herein in the preparation of tandem solar cells with improved photoelectric performance.

[0076] In some embodiments, the present invention provides the use of the compound of formula A and optional organic ammonium salt described in any embodiment herein in the preparation of a passivation layer, or in the preparation of a perovskite thin film containing the passivation layer.

[0077] In this invention, the photoelectric properties include, but are not limited to, open-circuit voltage and fill factor. Compared to tandem solar cells without a passivation layer, the open-circuit voltage of the tandem solar cells of this invention can be increased by ≥14mV, for example, 14-25 mV; the fill factor can be increased by ≥0.71%, for example, 0.71%-2.21%.

[0078] The present invention will be described below by way of specific embodiments. It should be understood that these embodiments are merely illustrative and are not intended to limit the scope of the invention. The methods, reagents, and materials used in the embodiments are conventional methods, reagents, and materials in the art, unless otherwise stated. The raw material compounds in the embodiments are all commercially available.

[0079] Cl-PTCDA (1,6,7,12-tetrachloro-3,4,9,10-tetracarboxylic dianhydride): Shanghai Aladdin Biochemical Technology Co., Ltd., CAS No.: 156028-26-1.

[0080] Example 1

[0081] (1) After cleaning the HJT crystalline silicon bottom cell with the textured surface with an N2 gun, treat it with UV ozone for 15 minutes before use.

[0082] (2) Hole transport material MeO-2PACz was deposited on the surface of the bottom cell by spin coating. The spin coating conditions were 4000r, 30s, and the concentration of MeO-2PACz was 0.5mmol / ml. The hole transport layer was then annealed at 100℃ for 30min.

[0083] (3) A perovskite layer was prepared by spin coating. Solid powders CsI, MABr, FAI, PbBr2, and PbI2 were dissolved in 800 μL of DMF and 200 μL of DMSO to obtain a perovskite solution. The mass concentrations of CsI, MABr, FAI, PbBr2, and PbI2 were 22.08 mg / mL, MABr, FAI, and PbBr2, respectively. The mass concentration of bI2 was 559.57 mg / ml. The solution was then deposited on the surface of the hole transport layer by spin coating under the following conditions: 1000 r / s for 10 s; 2000 r / s for 40 s; 6000 r / s for 20 s. 200 μL of antisolvent CB was added at 45 s to prepare a perovskite wet film. The perovskite wet film was then annealed in a glove box at 100 °C for 20 min to obtain a perovskite thin film (perovskite absorber layer).

[0084] (4) Cl-PTCDA (1,6,7,12-tetrachloro-3,4,9,10-tetracarboxylic dianhydride) and PDADI were deposited on the surface of the perovskite absorber layer using a co-evaporation method, wherein the mass ratio of Cl-PTCDA to PDADI was 1:2. Cl-PTCDA and PDADI were placed in two crucibles respectively, and after adjusting the corresponding rates under the same conditions, they were co-evaporated, wherein the evaporation rate of PCDA was 0.05 Å / s, the evaporation rate of PDADI was 0.1 Å / s, and the co-deposited thickness was 2 nm. The deposited silicon wafer was annealed at 100°C for 5 min under a N2 atmosphere to obtain a perovskite film containing a passivation layer.

[0085] (5) A 20 nm electron transport layer C60 was deposited on the surface of the passivation layer by evaporation. (6) A 15 nm buffer layer of SnO2 was deposited on the C60 surface using atomic layer deposition. (7) A 50 nm transparent electrode IZO was deposited on the SnO2 surface using magnetron sputtering; (8) Ag metal electrode layers with a thickness of 200 nm were prepared on the upper and lower surfaces of the device by thermal evaporation to complete the preparation of the tandem battery.

[0086] Example 2

[0087] The only difference between Example 2 and Example 1 is that only PTCDA was used to prepare the passivation layer, and PDADI was not used.

[0088] Example 3

[0089] The only difference between Example 3 and Example 1 is that the Cl-PTCDA in Example 1 is replaced with bromine-substituted PTCDA.

[0090] Example 4

[0091] The only difference between Example 4 and Example 1 is that the tetrachloro-substituted PTCDA in Example 1 is replaced with dichloro-substituted PTCDA (1,6-dichloro-3,4,9,10-tetracarboxylic dianhydride).

[0092] Example 5

[0093] The only difference between Example 5 and Example 1 is that the tetrachloro-substituted PTCDA in Example 1 is replaced with hexachloro-substituted PTCDA (1,4,6,9,11,14-hexachloro-3,4,9,10-tetracarboxylic dianhydride).

[0094] Example 6

[0095] The only difference between Example 6 and Example 1 is that the mass ratio of Cl-PTCDA to PDADI is 1:1.

[0096] Example 7

[0097] The only difference between Example 7 and Example 1 is that the mass ratio of Cl-PTCDA to PDADI is 1:30.

[0098] Comparative Example 1

[0099] The difference between Comparative Example 1 and Example 1 is that Cl-PTCDA was not used to prepare the passivation layer.

[0100] Comparative Example 2

[0101] The difference between Comparative Example 2 and Example 1 is that the Cl-PTCDA in Example 1 was replaced with halogen-free substituted PTCDA to prepare passivation.

[0102] Test Example 1

[0103] The solar cells prepared in Examples 1-7 and Comparative Examples 1-2 were subjected to photoelectric testing. The test temperature was 25±1℃. The current density-voltage (JV) curves of the devices were obtained using a source meter (Keithley 2400) on a solar simulator (SS-PST100R) at AM1.5G (100mW / cm²). 2 Obtained under illumination, the battery area is 1.05 cm². 2 Before testing, the light intensity was calibrated using a standard silicon cell, and the scan rate was 20mV / s.

[0104] The open-circuit voltage Voc is the terminal voltage of the cell in the open-circuit state. The short-circuit current Jsc is the current density that the perovskite solar cell can generate under short-circuit conditions. The fill factor F is the ratio of the maximum power of the solar cell to the product of the open-circuit voltage and the short-circuit current. The photoelectric conversion efficiency PCE can be calculated by measuring the current density-voltage curve (J-V curves) of the solar cell. The results are shown in Table 1 below.

[0105] Table 1. Photoelectric test results

[0106] As shown in Table 1, compared with Comparative Examples 1 and 2, the open-circuit voltages Voc and FF of Examples 1-6 are significantly improved.

[0107] Although the present invention has been disclosed above with reference to preferred embodiments, it is not intended to limit the present invention. Any person skilled in the art can make various modifications and alterations without departing from the spirit and scope of the present invention. Therefore, the scope of protection of the present invention should be determined by the claims.

Claims

1. A stacked battery, characterized in that, The stacked solar cell includes at least one perovskite sub-cell, the perovskite sub-cell including a perovskite absorber layer and a passivation layer disposed on the perovskite absorber layer, the passivation layer containing a compound of formula A: ； Among them, R1 and R2 are each independently selected from O, NH, CH2 or S; Where X is a halogen; n is 0, 1 or 2.

2. The stacked battery as described in claim 1, characterized in that: In equation A, R1 and R2 may be the same or different; In formula A, X is selected from one or more of Cl, Br, and I; In formula A, the number of X is 1-8, preferably 2-6.

3. The stacked battery as described in claim 1, characterized in that, The compound of formula A has the following structure, A-1: ； Where X is Cl and / or Br; n is 0, 1 or 2; the number of X is 1-8.

4. The stacked battery as described in claim 3, characterized in that, Compound A has the structure shown in Formula A-2: ； Wherein, X is selected from Cl and / or Br.

5. The stacked battery as described in claim 1, characterized in that, The passivation layer also contains an organic ammonium salt; the mass ratio of compound A to the organic ammonium salt is 1:(1-50).

6. The stacked battery as described in claim 5, characterized in that, The organic ammonium salt is selected from organic ammonium iodide salts and / or organic ammonium hydrochloride salts.

7. The stacked battery as described in claim 6, characterized in that, The organic ammonium salt is selected from one or more of propylenediamine iodine, phenylethylamine iodide, 4-trifluoromethyl-aniline hydrochloride, 2-thiophene ethylamine hydrochloride, ethylamine hydrochloride, and n-butylamine hydrochloride.

8. The stacked battery as described in claim 1, characterized in that, The perovskite sub-cell includes a hole transport layer, a perovskite absorber layer, a passivation layer, an electron transport layer, a buffer layer, a transparent electrode, and a metal electrode arranged sequentially.

9. The stacked battery as described in claim 1, characterized in that, The tandem battery is a tandem perovskite-crystalline silicon battery.

10. The stacked battery as described in claim 9, characterized in that, The stacked solar cell includes a crystalline silicon base cell and a perovskite sub-cell. The perovskite sub-cell includes a hole transport layer, a perovskite absorption layer, a passivation layer, an electron transport layer, a buffer layer, a transparent electrode, and a metal electrode arranged sequentially. The hole transport layer is located on the side closest to the crystalline silicon base cell.

11. A method for preparing a stacked battery as described in claim 1, characterized in that, The method includes: depositing a passivation material containing a compound of formula A on the surface of the perovskite absorber layer of the perovskite sub-cell, and annealing it to obtain the passivation layer.

12. The method as described in claim 11, characterized in that, The deposition method is evaporation; and / or The annealing conditions are as follows: annealing in an inert atmosphere at a temperature of 80-120℃.

13. The method as described in claim 11, characterized in that, The method includes: depositing a passivation material containing a compound of formula A and an organic ammonium salt onto the surface of a perovskite absorber layer using a co-evaporation method, followed by annealing to obtain the passivation layer.

14. The method as described in claim 11, characterized in that, The method further includes: providing a crystalline silicon bottom cell before preparing the passivation layer, and sequentially depositing a hole transport layer and a perovskite light-absorbing layer on the surface of the crystalline silicon bottom cell; and sequentially depositing an electron transport layer, a transparent electrode, and a metal on the surface of the passivation layer after preparing the passivation layer.

15. The application of the compound of formula A as described in claim 1 in the preparation of tandem solar cells with improved photoelectric performance.

16. The application as described in claim 15, characterized in that, Application of compound A and organic ammonium salt in the preparation of tandem solar cells with improved photoelectric performance.

17. The application as described in claim 15, characterized in that, The use of the compound of formula A and the optional organic ammonium salt in the preparation of a passivation layer, or in the preparation of a perovskite thin film containing the passivation layer.

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