Effect of Dispersion Solutions on Optical Properties and Stability of CsPbBr 3 Perovskite Nanocrystals

Abstract

Long-term storage stability of cesium lead-based perovskite nanocrystals, especially at ambiance conditions is a vital challenge that deters their advancement in photovoltaic applications. Herein, CsPbBr 3 perovskite nanocrystals are synthesized by hot injection method and the stability of CsPbBr 3 nanocrystals is investigated when dispersed in individual solvents such as Toluene, Acetone, and Ethanol as well as the combination of solvents. The synergistic effect of toluene- non-polar molecule and acetone-a polar molecule was studied and their effect on the stability of CsPbBr 3 in terms of retention of optical absorption and emission is investigated. A combination of toluene and acetone as solvents is found to be the best medium for dispersion of CsPbBr 3 perovskite nanocrystals which remain stable for two weeks with 63%, 60% retention of luminescence and absorbance. Further, by the addition of PVP polymer (0.05 wt%) in dispersion solution, the luminescence and absorbance are retained up to ∼77% and ∼70% for more than two months of storage time. The storage stability of a combination of mix solvents is important for the applications in which stable dispersion of perovskite materials ought to prepare in polar or non-polar solvents.