APL Materials (Mar 2020)
An experimental study on the blinking suppression mechanism of organic-inorganic formamidinium lead halide perovskite quantum dots on N-Type semiconductors
Abstract
Lead halide perovskite has emerged as a potential material for a wide range of applications, including solar cells, light-emitting diode displays, lasing, and single photon emitters. To optimize their utilization in optoelectronic devices, the fundamental photophysical properties, especially their charge carrier transition and blinking behaviors, must be elucidated. In this study, we investigate the blinking behaviors of single formamidinium bromide perovskite quantum dots (FAPbBr3 PQDs) on the n-type TiO2 substrate. It is suggested that the electrons from TiO2 fill the trap states of FAPbBr3 PQD during Fermi-level equilibrium, which can reduce the possibility of capturing the hot electrons from PQD into the trap states. In addition, charge separation and charge recombination processes between PQD and TiO2 are expected to shorten the duration of the OFF state, thus stabilizing the fluorescence of PQDs.