Quantum dot and electron acceptor nano-heterojunction for photo-induced capacitive charge-transfer

Abstract Capacitive charge transfer at the electrode/electrolyte interface is a biocompatible mechanism for stimulation of neurons. Although quantum dots showed their potential photostimulation device architectures, dominant photoelectrochemical combined with heavy-metal content in such architectures hinders safe use. In this study, we demonstrate heavy-metal-free dot-based nano-heterojunction devices that generate capacitive photoresponse. For that, formed novel form nano-heterojunctions using type-II InP/ZnO/ZnS core/shell/shell dot as donor and fullerene derivative PCBM electron acceptor. The reduced electron–hole wavefunction overlap 0.52 due to band alignment passivation trap states indicated by high photoluminescence yield 70% led domination photoinduced an optimum donor–acceptor ratio. This study paves way toward efficient nanoengineered next-generation devices.