Photoexcited electron transfer in hydrophobic fluorescent FAPbBr₃ perovskite nanocrystals and graphene heterostructures

Heterostructures of multidimensional perovskite materials possess enormous potential for use in optoelectronic devices and are also vital for enlightening the phenomenon of charge transfer (CT) across the interface of the heterostructures. In this article, we present the fabrication of FAPbBr₃ nanocrystals (NCs) and graphene heterostructures and study the CT dynamics in donor (FAPbBr₃ NCs)-acceptor (graphene). The photoluminescence (PL) quenching of FAPbBr₃ NCs with successive addition of graphene confirms the quenching ability of graphene. The transfer of the photoexcited electron from NCs to the graphene is responsible for quenching of PL that is supported by time-resolved photoluminescence (TRPL) and cyclic voltammetric (CV) analysis. The electron transfer occurs through type-I band alignment of NCs and graphene. Reduction of CT resistance at the interface make the electron transfer easier as assessed by electrochemical impedance spectroscopy (EIS) analysis. Such heterostructures exhibiting facile electron transfer could make efficient commercial antenna systems for optoelectronic devices. Graphical Abstract: (Figure presented.)