CN-115347071-B - Silicon/perovskite three-terminal laminated solar cell structure and preparation method thereof

CN115347071BCN 115347071 BCN115347071 BCN 115347071BCN-115347071-B

Abstract

The invention discloses a silicon/perovskite three-terminal laminated solar cell structure and a preparation method thereof, the silicon/perovskite three-terminal laminated solar cell comprises a perovskite top layer solar cell unit and a back contact silicon solar cell unit. The perovskite top layer solar cell unit comprises a first metal electrode layer, a first reflection reducing layer, a first transparent conductive oxide layer, a first transparent oxide buffer layer, a first transmission layer, a first passivation layer, a perovskite absorption layer and a second transmission layer which are sequentially arranged from top to bottom. The silicon bottom battery and the perovskite top battery of the silicon/perovskite three-terminal laminated solar cell have three-terminal laminated cell structures, are not required to meet the requirement of current matching by the laminated cells at two ends, can obtain higher photoelectric conversion efficiency than the sub-cells, and are simple in preparation process and low in preparation cost.

Inventors

YANG YING
ZHOU YURONG
SHANG JIACHENG
WANG QI

Assignees

中国科学院大学

Dates

Publication Date: 20260512
Application Date: 20210513

Claims (6)

1. A silicon/perovskite three-terminal laminated solar cell is characterized by comprising a bottom cell and a top cell from bottom to top in sequence, The top battery is a perovskite solar cell unit and comprises a first metal electrode layer, a first reflection reducing layer, a first transparent conducting layer, a first transmission layer, a first passivation layer, a perovskite absorption layer and a second transmission layer from top to bottom; The silicon substrate battery unit of the back contact structure comprises a second passivation layer, a silicon substrate, a third transmission layer, a fourth transmission layer, a second metal electrode layer and a third metal electrode layer, wherein the third transmission layer and the fourth transmission layer are respectively an electron transmission layer and a hole transmission layer of the silicon substrate battery and are both positioned on the back surface of the silicon substrate battery; The first metal electrode layer, the second metal electrode layer and the third metal electrode layer form a three-terminal output structure.
2. The three terminal stacked silicon/perovskite solar cell according to claim 1, wherein the top cell further comprises a first buffer layer and/or the bottom cell further comprises a further second passivation layer.
3. The three-terminal stacked silicon/perovskite solar cell according to claim 1, wherein the first and second transport layers are respectively an electron transport layer and a hole transport layer of a perovskite top cell or respectively a hole transport layer and an electron transport layer, wherein the electron transport layer is made of any one of titanium dioxide (TiO 2 ), tin dioxide (SnO 2 ), zinc oxide (ZnO) and carbon 60 (C60), and the hole transport layer is made of any one of cuprous iodide (CuI), nickel oxide (NiO x ) and copper thiocyanate (CuSCN).
4. The three-terminal stacked silicon/perovskite solar cell according to claim 1, wherein the silicon substrate is an n-type crystalline silicon or p-type crystalline silicon substrate, and is any one of a double-sided polished type, a single-sided textured type or a double-sided textured type.
5. The silicon/perovskite three-terminal stacked solar cell according to claim 1, wherein the second passivation layer is required to passivate defects on the surface of the crystalline silicon substrate, and the passivation layer is made of any one of amorphous silicon, silicon oxide and aluminum oxide materials.
6. The three-terminal stacked silicon/perovskite solar cell according to claim 1, wherein the third and fourth transport layers are an electron transport layer and a hole transport layer of a crystalline silicon bottom cell, wherein the electron transport layer is made of any one of n-type silicon, titanium dioxide (TiO 2 ), zinc oxide (ZnO), and tin dioxide (SnO 2 ), and the hole transport layer is made of any one of p-type silicon, molybdenum trioxide (MoO 3 ), tungsten trioxide (WO 3 ), and vanadium oxide (VO x ).

Description

Silicon/perovskite three-terminal laminated solar cell structure and preparation method thereof Technical Field The invention relates to the technical field of solar cell structural design and production and preparation, in particular to a structure of a silicon/perovskite laminated cell and a preparation method thereof. Background Perovskite solar cells are a research hotspot in the photovoltaic field in recent years, and the efficiency of the perovskite solar cells is improved from less than 3% to 25.5% in a short period of 10 years, so that the perovskite solar cells are the solar cells with the fastest efficiency improvement. The perovskite material and the perovskite device have the advantages of good comprehensive performance, high extinction coefficient, proper band gap width, higher open-circuit voltage and other physical characteristics, and the perovskite material has a simple structure in production and preparation, mild preparation conditions and simple preparation process, so that the perovskite material is widely focused. While it is not easy to greatly improve the efficiency of single crystal silicon or perovskite cells by limiting the SQ theoretical efficiency limit, combining the two to form a stacked cell is expected to make the conversion efficiency break through the SQ limit of single crystal cells. Silicon largely converts the infrared/near infrared of sunlight into electrical energy, while perovskite compounds make use of the visible part of the spectrum. Thus, stacked solar cells made of silicon and perovskite may achieve higher efficiencies than single cells alone. The perovskite/silicon laminated cell reported in the prior study generally adopts a two-end structure with a top cell and a bottom cell connected in series, or a four-end structure with the top cell and the bottom cell independent of each other, as shown in fig. 1 and 2. According to the change relation of the theoretical ultimate efficiency of the cells along with the band gap of the top cell light absorbing layer, the optimal band gap of the top cell light absorbing layers of the cells at two ends is 1.73eV, and the optimal band gaps of the top cell light absorbing layers of the cells at three ends and four ends are 1.8eV. As shown in fig. 1, a schematic structure of a silicon/perovskite stacked cell having two ends is shown. The two-end battery comprises a metal electrode A, a transparent conductive layer B, a perovskite absorption layer C, a tunneling layer D, a silicon battery E and a back electrode F from top to bottom in sequence. The theoretical ultimate efficiency of the two-end cells varies obviously with the band gap of the top cell, so that doping is required to regulate the band gap of the perovskite material to be about 1.6-1.8 eV. And the transparent conductive layer and the emitter in the battery structure at two ends have certain parasitic absorption on the back surface field layer, which can affect the efficiency of the device. And because the top battery and the bottom battery are in a series structure, the spectra are required to be reasonably distributed, so that the currents of the top battery and the bottom battery are matched, and the maximum output current is achieved, namely, the two sub-batteries are mutually limited, and the final output current takes the sub-battery with smaller current as a reference, so that the perovskite material selection and thickness and other conditions are limited to a certain extent. As shown in fig. 2, a schematic structure of a silicon/perovskite stacked cell having four ends is shown. The four-terminal structure comprises two mechanically stacked sub-cell structures, wherein the two sub-cells are independently placed and connected, can be independently kept at a maximum power point, and the top cell and the bottom cell are connected through a tunneling junction with high efficiency, so that more photons can reach the bottom cell. The top cell mainly comprises a transparent conductive layer B, a perovskite absorption layer C and a transparent conductive layer G from top to bottom. The bottom cell mainly comprises a metal electrode H, a transparent conductive layer K, a silicon cell E and a back electrode F from top to bottom. The two sub-cells of the four-terminal cell do not affect each other in the preparation process, and the condition of current matching does not need to be satisfied. However, transparent conductive layers are used as electrode materials on both sides of the top cell and the light receiving surfaces of the bottom cell of the four-terminal cell, which is not beneficial to the reduction of the cell cost. Disclosure of Invention The invention aims to solve the technical problem of providing a structure and a preparation method for preparing a three-terminal laminated solar cell, wherein the three-terminal laminated solar cell is prepared by taking a back contact crystalline silicon solar cell as a bottom cell and combining a wide band gap perovski