Improved flexible ZnO/CsPbBr3/Graphene UV photodetectors with interface optimization by solution process

Abstract

Flexible and wearable photodetectors (PDs) that can be directly equipped on human bodies have attracted extensive attention due to their great potential in communication, health and safety applications. However, low flexibility and complicated fabrication process hinder the development of fiber- and textile-PDs for practical applications. Here, we use an efficient solution strategy to integrate CsPbBr3 nanosheets (NSs) into conventional ZnO nanowires (NWs)/graphene flexible thin film PDs based on PVDF substrate. Compared with the simpler ZnO NWs/graphene structure, the built-in electric field of ZnO/CsPbBr3 PN junction can facilitate the separation and transport of the photo-generated carriers. Moreover, the ZnO networks filled with CsPbBr3 NSs result in a smooth interface and close contacts with graphene. With the interface optimization, the enhanced transport efficiency of the carriers further leads to a high Ilight/Idark ratio of ∼103. In addition, such PVDF based PDs exhibit excellent flexibility, demonstrating great potential for practical flexible optoelectronics.