Study on fluorescence properties and stability of Cu2+-Substituted CsPbBr3 perovskite quantum dots

Abstract

The toxicity and stability of all-inorganic perovskite quantum dots are major challenge to be addressed in its commercialization process. Here, the toxicity of lead is reduced while improving the optical properties of quantum dots via replacing Pb2+ ions in CsPbBr3 perovskites quantum dots with low-toxicity and cost-effectiveness Cu2+ cations. The PL emission and absorption peaks of quantum dots appear blue shift due to lattice shrinkage caused by copper ion doping. At the same time, we also observed that with the increase of Cu2+ doping concentration, the fluorescence lifetime of quantum dots decreased from 40.66 ns to 8.23 ns. Next, the slim CsPbBr3:Cu@SiO2 core-shell QDs were synthesized via a simply one-step synthesis method. Compared with the original CsPbBr3:Cu QDs, the stability of the quantum dots after coated has been significantly improved. Benefiting from this effective cladding strategy, these CsPbBr3:Cu@SiO2 can be well used for manufacturing high-performance perovskite LEDs.