CN-122028636-A - Ultra-wide band-gap perovskite film and application thereof

Abstract

The invention discloses an ultra-wide band-gap perovskite film and application thereof, and belongs to the technical field of solar cells. The ultra-wide band-gap perovskite film is prepared by coating perovskite precursor liquid, performing post-treatment on a perovskite wet film by using an inducer, and then annealing to obtain the perovskite film, wherein the inducer is selected from oleylamine chloride, methylamine chloride, formamidine chloride, guanidine chloride, octyl ammonium chloride, dodecyl trimethyl ammonium chloride, cetyl trimethyl ammonium chloride, octadecyl trimethyl ammonium chloride, dimethyl dioctadecyl ammonium chloride ‌ and ‌ tetradecyl trimethyl ammonium chloride ‌. According to the invention, the chlorine source is introduced as an inducer, and the post-treatment is carried out in the wet state of the film, so that the homogenization of the film surface is realized, the problem of wrinkles caused by the high fluctuation of the ultra-wide band gap perovskite surface can be effectively solved, and a new solution is provided for the preparation of the high-efficiency and stable all-perovskite three-junction solar cell.

Inventors

• TAN HAIREN
• LIU HAONAN
• ZHANG YUHONG
• LIN RENXING
• LIU YE

Assignees

• 南京大学
• 仁烁光能(苏州)有限公司

Dates

Publication Date

20260512

Application Date

20260116

Claims (8)

1. 1. A perovskite thin film, characterized in that it is prepared by the following method: coating perovskite precursor liquid, performing aftertreatment on a perovskite wet film by using an inducer, and then annealing to obtain the perovskite film; The inducer is selected from oleylamine chloride, methylamine chloride, formamidine chloride, guanidine chloride, octylammonium chloride, dodecyltrimethylammonium chloride, cetyltrimethylammonium chloride, octadecyltrimethylammonium chloride, dimethyl dioctadecyl ammonium chloride ‌, ‌ tetradecyltrimethylammonium chloride ‌.
2. 2. The perovskite thin film of claim 1, wherein the perovskite precursor solution comprises a precursor of a perovskite structure substance and a solvent, the perovskite structure substance having a band gap of 1.9-2.2eV.
3. 3. The perovskite thin film according to claim 2, wherein the perovskite structure substance has a chemical formula of ABX 3 , a is a monovalent cation selected from one or more of cesium ion, rubidium ion, methylamine ion, formamidine ion, B is a divalent cation selected from one or more of lead ion, copper ion, zinc ion, gallium ion, tin ion, calcium ion, and lanthanide metal, and X is a monovalent anion selected from one or more of iodide ion, bromide ion, chloride ion, fluoride ion, and thiocyanate ion.
4. 4. The perovskite thin film according to claim 2, wherein the solvent is selected from one or more of N, N-dimethylformamide, dimethyl sulfoxide, acetonitrile, 2-methoxyethanol, N-methylpyrrolidone.
5. 5. The perovskite thin film of claim 1, wherein the coating is spin coating, slot coating, or knife coating.
6. 6. The perovskite thin film of claim 1, wherein the annealing is at a temperature of 85 to 135 ℃ for a time of 10 to 30 minutes.
7. 7. A solar cell comprising the perovskite thin film of any one of claims 1 to 6.
8. 8. The solar cell of claim 7, wherein the solar cell is a full perovskite triple junction tandem solar cell.

Description

Ultra-wide band-gap perovskite film and application thereof Technical Field The invention belongs to the technical field of solar cells, and particularly relates to an ultra-wide band-gap perovskite film and application thereof in a full perovskite three-junction laminated solar cell. Background Perovskite-based high efficiency stacked solar cells are largely divided into two categories, the first one that combines perovskite cells with other cells (e.g., crystals Si, CIGS, OPV) and the second one that directly combines perovskite with perovskite (all-perovskite) cells. Although perovskite and other batteries can be combined to prepare a high-efficiency laminated device, the preparation cost of preparing laminated batteries by combining different photovoltaic technologies is high, the process is complex and the compatibility is poor. In contrast, the all-perovskite stacked device has the characteristics of high efficiency, low cost, small influence on the environment and the like, is considered to be one of high-efficiency low-cost photovoltaic technologies with great potential, and will take an important leading position in future photovoltaic power generation technologies. Currently, the authentication efficiency of a full perovskite two-junction stacked solar cell has reached 30.1% which is far higher than that of a single perovskite solar cell. One simple way to push the efficiency to higher values is to add a third subcell to the full perovskite two-junction series device to construct a three-junction stacked cell to further reduce carrier heat loss. The full perovskite three-junction series battery at the present stage is an emerging research direction in the field of recent perovskite batteries, and the reported research results at home and abroad are relatively few. In an actual triple-junction device, the efficiency improvement amplitude is gradually reduced, mainly due to the increase of the number of intermediate composite layers and interface layers of the triple-junction structure, and the requirement on current matching among all sub-cells is higher, so that the accumulation effects of optical loss and parasitic absorption are easily introduced, and the overall performance improvement is limited. At present, perovskite with different forbidden bandwidths can be reasonably designed through component engineering, a narrow bandgap sub-cell is used as a bottom cell and is mainly responsible for high-efficiency utilization of near infrared light, a middle bandgap sub-cell is used as a middle cell and corresponds to a visible light wave band, and an ultra-wide bandgap top cell positioned at the uppermost layer needs to have a larger band gap so as to effectively absorb high-energy shortwave photons. On the basis, all the junction sub-cells are matched together in a synergistic way, and the high-efficiency full perovskite three-junction laminated solar cell is constructed while the structural complexity of the device is considered. In the above structure, the ultra-wide band gap perovskite subcell device performance as a top cell directly affects the spectral matching effect and overall output performance of the three-junction stacked device. Therefore, how to prepare a stable and high-efficiency ultra-wide band-gap perovskite subcell is one of the technical problems to be solved in the field of the current all-perovskite three-junction stacked solar cell. However, the research on ultra-wide band-gap perovskite subcells in the prior art still has the disadvantage that the related problems are mainly manifested in three aspects, namely, light-induced halogen phase separation. Generally, light induced halogen phase separation is commonly found in wide band gap iodine (I), bromine (Br) mixed perovskite absorber layers with band gaps greater than 1.65 eV. Particularly, for an ultra-wide band-gap perovskite absorption layer with a band gap of about 2.0 eV, the phase separation of halogen is easy to occur because the perovskite absorption layer generally has a Br content higher than 60%, and the band gap of a formed I-rich region is low, so that the perovskite absorption layer becomes a recombination center and enhances the non-radiative recombination of carriers. And secondly a large open circuit voltage (V oc) loss. The actual V oc of an ultra-wide band gap subcell is typically significantly different from its theoretical value. The actual ultra-wide band gap V oc tends to have a large loss, and the main reason is that the perovskite absorbing layer with high Br content is easy to generate lattice strain and generate halogen vacancies, so that defects are formed to reduce the service life of carriers. In addition, large V oc losses exceeding 700 mV are also caused by photo-induced phase separation, directly leading to degradation of the final device performance. And finally, the problems of current mismatch and interconnection loss in the all-perovskite three-junction laminated solar cell constructed by