New materials make solar energy more capable

Photoelectric conversion efficiency of inorganic perovskite solar cells using new electron-transporting materials

Solar cell is an important product that converts solar energy into electrical energy and realizes energy saving and emission reduction. Since it was first applied to the field of solar power in 2009, perovskite is considered to have great commercial value based on its excellent performance and low cost. Perovskite solar cells have also received increasing attention and popularity. So, can perovskite solar cells further improve the photoelectric conversion efficiency and make solar energy more "energy"? Recently, Li Zhenxing, an associate researcher at the School of New Energy and Materials, China University of Petroleum (Beijing), conducted in-depth research on the electron transmission materials of perovskite solar cells, and designed a new type of electron transmission material with a photoelectric conversion efficiency higher than that of traditional electrons. Transmission material increased by 40%.

For perovskite solar cells, the electron transport material is an important factor that determines the photoelectric conversion efficiency. Li Zhenxing collaborated with Yang Yang, a professor at the University of California, Los Angeles, and Wang Zhaokui, a professor at Suzhou University, to conduct in-depth research on the electron transport materials of perovskite solar cells, and designed a new type of electron transport material, tin oxide coated zinc oxide, by the solvothermal method Core-shell nanostructure (ZnO @ SnO2). The research result was published in the internationally renowned academic journal "The Journal of the American Chemical Society" titled "Tin Oxide Coated Zinc Oxide Core-Shell Nanoparticles Effectively Improve the Photoelectric Conversion Efficiency of Inorganic Perovskite Solar Cells."

The research results for the first time proposed the preparation method of tin oxide-coated zinc oxide core-shell nanostructures, revealing its inherent mechanism of higher photoelectric conversion efficiency. Due to the energy level matching of the SnO2 shell layer and the high electron mobility of the core layer ZnO nanoparticles, the photoelectric conversion efficiency of inorganic perovskite solar cells is as high as 14.35%. The size of ZnO @ SnO2 core-shell nanoparticles is 8.1 nm, and the electron mobility is 7 times that of SnO2 nanoparticles. At the same time, the uniform core-shell type ZnO @ SnO2 nanoparticles are extremely beneficial to the growth of inorganic perovskite films. These results indicate that tin oxide-coated zinc oxide core-shell nanostructures are an ideal electron transport layer for solar cells, and the photoelectric conversion efficiency is 40% higher than traditional electron transport materials. (Ji Hongmei)