Charge Transfer in the Heterostructure of CsPbBr3 Nanocrystals with Nitrogen-Doped Carbon Dots.

Abstract

Heterostructures of inorganic halide perovskites with mixed-dimensional inorganic nanomaterials have shown great potential not only in the field of optoelectronic energy devices and photocatalysis but also for improving our fundamental understanding of the charge transfer across the heterostructure interface. Herein, we present for the first time the heterostructure integration of the CsPbBr3 nanocrystal with an N-doped carbon dot. We explore the photoluminescence (PL) and photoconductivity of the heterostructure of CsPbBr3 nanocrystals and N-doped carbon dots. PL quenching of CsPbBr3 nanocrystals with the addition of N-doped carbon dots was observed. The photoexcited electrons from the conduction band of CsPbBr3 are trapped in the N-acceptor state of N-doped carbon dots, and the charge transfer occurs via quasi type II-like electronic band alignment. The charge transfer in the halide perovskite-based heterostructure should motivate further research into the new heterostructure synthesis with perovskites and the fundamental understanding of the mechanism of charge/energy transfer across the heterostructure interface.