Controllable Vapor Growth of CsPbBr3/CdS 1D Heterostructures with Type-II Band Alignment for High-Performance Self-Powered Photodetector

The controllable growth of semiconductor heterostructures with suitable band alignment and morphology is crucial to construct high-performance optoelectronic devices, which is limited to the traditional semiconductor families. Here, high-quality CsPbBr3/CdS heterostructures with the unique 1D morphology and type-II band alignment have been obtained through a 2-step physical vapor deposition (PVD) strategy, in which CsPbBr3 microcubes were grown on the side wall of the pre-grown free-standing CdS microwires. Owing to the effective separation and transportation of photogenerated carriers at the CsPbBr3/CdS heterojunction with type-II band alignment, the photodetector based on a single CsPbBr3/CdS 1D heterostructure showed high self-powered performances (without additional bias supplies), including Ion/Ioff ratio of 3×103, photoresponsivity of 24.5 mA/W, detectivity of 1.09×1012 Jones, detectable spectral ranging from 350 nm to 530 nm and respond speeds of 1.5 ms (rise time) and 14.9 ms (decay time) at the bias of 0 V. This work provides an effective way to the controllable growth of high-quality CsPbX3-based 1D heterostructures, which promotes their practical applications in optoelectronic devices without power consumption.