CN-122028634-A - B-site Cd-doped two-dimensional perovskite thin film and perovskite/crystalline silicon laminated solar cell

Abstract

The invention provides a B-site Cd doped two-dimensional perovskite thin film and a perovskite/crystal silicon laminated solar cell, and belongs to the technical field of solar cells. The method realizes two key targets by regulating and controlling chemical components of the two-dimensional perovskite, namely, on one hand, the Cd is utilized to replace Pb partially, the band gap is accurately regulated and controlled to be 1.6-1.8 eV, the spectrum absorption requirement of a laminated top battery is met, on the other hand, the mixed cations at the R position and the A position are relied on to stabilize a layered structure, and meanwhile, the charge transport performance is optimized through orbital hybridization of Cd and Pb, so that the stability of the film is improved, and the preparation process environment of a silicon substrate is adapted. Finally, the two-dimensional perovskite film is used as a top battery light absorption layer of a perovskite/crystalline silicon laminated solar cell, solves the problems of the existing laminated device such as mismatching of band gaps, insufficient stability and poor compatibility with a silicon substrate, and provides a key material and a preparation method support for the industrialized promotion of laminated photovoltaic technology.

Inventors

• CAI MOLANG
• SHEN WENZHONG
• SHA SHI
• ZHANG YONG
• GUO XINWEI

Assignees

• 蔡墨朗
• 沈文忠
• 沙湜
• 张勇
• 郭欣维

Dates

Publication Date

20260512

Application Date

20251231

Claims (10)

1. 1. The B-site Cd-doped two-dimensional perovskite thin film is characterized in that the chemical composition of the B-site Cd-doped two-dimensional perovskite is R 2 A n-1 B n X 3n+1 , wherein n=1, 2 or 3; The R position is an organic ammonium cation; the A position is one or more of methylamine cations, formamidine cations and cesium cations; A mixture of Cd 2+ and Pb 2+ at position B, the molar content of Cd in position B >0 and <100%; The X position is I - or a mixture of I - and Br - .
2. 2. The B-site Cd doped two-dimensional perovskite thin film according to claim 1, wherein the organic ammonium cation at the R-site is one or more of a butyl ammonium cation, a 2-methoxyethyl ammonium cation, a 2-methylthioethyl ammonium cation, a benzalkonium cation, a phenethyl ammonium cation, and a 2-thiophenecammonium cation.
3. 3. The B-site Cd doped two-dimensional perovskite thin film according to claim 1 or 2, wherein the molar ratio of Cd 2+ to Pb 2+ in the B-site is 1:1-3.
4. 4. The preparation method of the B-site Cd-doped two-dimensional perovskite thin film according to any one of claims 1-3, which is characterized by comprising the following steps: Mixing raw materials with chemical compositions of RX, AX and BX with an organic solvent to obtain perovskite slurry; and coating the perovskite slurry on the surface of a substrate, and annealing to obtain the B-site Cd-doped two-dimensional perovskite film.
5. 5. The method according to claim 4, wherein the annealing is performed at a temperature of 100 to 150 ℃ for 20 to 40 minutes.
6. 6. The application of the B-site Cd-doped two-dimensional perovskite film prepared by any one of claims 1-3 or the preparation method of claim 4 or 5 in a solar cell top cell light absorption layer.
7. 7. The perovskite/crystalline silicon laminated solar cell is characterized by comprising a crystalline silicon bottom cell and a perovskite top cell laminated on the surface of the crystalline silicon bottom cell; The perovskite top battery comprises a tunneling composite layer, a hole or electron transport layer, a perovskite layer, an electron or hole transport layer and a transparent electrode layer which are sequentially stacked, wherein the perovskite layer is the B-site Cd doped two-dimensional perovskite film according to any one of claims 1-3 or the B-site Cd doped two-dimensional perovskite film prepared by the preparation method according to claim 4 or 5; and the outermost layers of the crystalline silicon bottom battery and the perovskite top battery are provided with metal grids.
8. 8. The perovskite/crystalline silicon tandem solar cell of claim 7 wherein the crystalline silicon bottom cell is one of HJT cells, TOPCon cells, IBC/BC cells, and BSF cells.
9. 9. The perovskite/crystalline silicon stacked solar cell according to claim 7, wherein in the perovskite top cell, the tunneling composite layer comprises one or more of IZO, ITO and AZO, and has a thickness of 2-100 nm; The hole transport layer is made of one or more of SAM, nickel oxide, spiro-OMeTAD and PTAA; The thickness of the perovskite layer is 400-2000 nm; The electron transport layer is made of one or more of PCBM, C 60 、TiO 2 and SnO 2 , and the thickness of the electron transport layer is 10-20 nm; The transparent electrode layer is made of one or more of IZO, ITO and AZO, and has a thickness of 60-100 nm.
10. 10. The method for manufacturing the perovskite/crystalline silicon stacked solar cell according to any one of claims 7 to 9, comprising the steps of: Sequentially depositing a tunneling composite layer, a hole or electron transport layer, a spin-coating perovskite layer, an electron or hole transport layer and a transparent electrode layer on the surface of the crystalline silicon bottom battery to obtain a perovskite top battery; And depositing metal grids on the outermost layers of the crystalline silicon bottom cell and the perovskite top cell to obtain the perovskite/crystalline silicon laminated solar cell.

Description

B-site Cd-doped two-dimensional perovskite thin film and perovskite/crystalline silicon laminated solar cell Technical Field The invention relates to the technical field of solar cells, in particular to a B-site Cd-doped two-dimensional perovskite thin film and a perovskite/crystalline silicon laminated solar cell. Background In the process of upgrading the photovoltaic technology to high efficiency and high stability, the perovskite/crystalline silicon laminated solar cell has become the core direction of breaking through the efficiency ceiling of the single-junction silicon cell by virtue of the synergistic advantage of 'the perovskite top cell absorbs short-wave visible light and the silicon bottom cell absorbs long-wave infrared light', and the highest efficiency of the laboratory is broken through by 35% at present, so that the perovskite/crystalline silicon laminated solar cell is the key research and development field of the next-generation commercial photovoltaic device. The top cell light absorption layer is used as a key component of a laminated structure, and three requirements of ' band gap precise matching (1.6-1.8 eV to avoid spectrum overlapping with a silicon bottom cell ', ' high environmental stability (tolerance to medium temperature and humidity conditions in the preparation process of the silicon cell) ' good compatibility with the silicon bottom ' are simultaneously met. The excellent stability of the quasi-two-dimensional perovskite due to the layered structure is one of the preferred materials for the top cell in perovskite/crystalline silicon stacked solar cells. In the prior art, lead-based 2DRP perovskite has been preliminarily applied in the fields of medium-low temperature solution preparation, flexible device integration and the like by optimizing the film crystallinity by regulating the chain length of an organic cationic layer (such as butylammonium BA and formamidine FA). But for the specific requirements of perovskite/crystalline silicon stacks, there are still technical bottlenecks of bandgap mismatch, insufficient stability, poor compatibility with silicon substrates. Disclosure of Invention In view of the above, the present invention aims to provide a B-site Cd-doped two-dimensional perovskite thin film and a perovskite/crystalline silicon stacked solar cell. The B-site Cd doped two-dimensional perovskite thin film provided by the invention has the advantages of accurate band gap regulation and control to a range of 1.6-1.8 eV, good stability and silicon substrate adaptation, and high short-circuit current density and high photovoltaic efficiency when being used as a perovskite/crystalline silicon laminated solar cell light absorption layer. In order to achieve the above object, the present invention provides the following technical solutions: The invention provides a B-site Cd-doped two-dimensional perovskite thin film, wherein the chemical composition of the B-site Cd-doped two-dimensional perovskite is R 2An-1BnX3n+1, wherein n=1, 2 or 3; The R position is an organic ammonium cation; the A position is one or more of methylamine cations, formamidine cations and cesium cations; A mixture of Cd 2+ and Pb 2+ at position B, the molar content of Cd in position B >0 and <100%; The X position is I - or a mixture of I - and Br -. Preferably, the organic ammonium cation at the R position is one or more of a butyl ammonium cation, a 2-methoxyethyl ammonium cation, a 2-methylthioethyl ammonium cation, a benzalkonium cation, a phenethyl ammonium cation and a 2-thiophen methyl ammonium cation. Preferably, the molar ratio of Cd 2+ to Pb 2+ in the B site is 1:1-3. The invention provides a preparation method of the B-site Cd doped two-dimensional perovskite film, which comprises the following steps: Mixing raw materials with chemical compositions of RX, AX and BX with an organic solvent to obtain perovskite slurry; and coating the perovskite slurry on the surface of a substrate, and annealing to obtain the B-site Cd-doped two-dimensional perovskite film. Preferably, the annealing temperature is 100-150 ℃ and the annealing time is 20-40 min. The invention provides application of the B-site Cd doped two-dimensional perovskite thin film in a solar cell top cell light absorption layer. The invention provides a perovskite/crystalline silicon laminated solar cell, which comprises a crystalline silicon bottom cell and a perovskite top cell laminated on the surface of the crystalline silicon bottom cell; the perovskite top battery comprises a tunneling composite layer, a hole or electron transport layer, a perovskite layer, an electron or hole transport layer and a transparent electrode layer which are sequentially laminated, wherein the perovskite layer is the B-site Cd doped two-dimensional perovskite film; and the outermost layers of the crystalline silicon bottom battery and the perovskite top battery are provided with metal grids. Preferably, the crystalline silicon bottom battery is one