Temperature Dependent Transient Photoconductive Response of CsPbBr₃ NCs

In recent years, all-inorganic cesium-lead halogenated perovskite CsPbX3 (X=Cl, Br, I) nanocrystalline (NCs) materials have become the focus of scientific research due to their unique properties such as long carrier life, strong light absorption, low-cost manufacturing, and band gap adjustability. However, the transient photoconductivity of CsPbBr3 nanocrystals have been hardly researched. In this work, CsPbBr3 nanocrystals were prepared by ligand-assisted re-precipitation method. Then their photoconductive sample preparation and test device of vacuum transient photoconductivity were improved. Effects of different temperatures and different excitation powers on transient photoconductivity of CsPbBr3 nanocrystals were studied. Experiment results show that the photo-generated current decay rate is gradually reduced within the temperature range from 133 K to 273 K, and increases gradually within the temperature range from 273 K to 373 K with temperature increasing. Results of excitation power-dependent show that the photo-generated current decay rate increases when the excitation power increases from 200 to 1000 mW. The research method of this study provides a new idea for studying the dynamics related behavior of photoexcited photo-generated carriers.