Visible-light photodetector with enhanced performance based on a ZnO@CdS heterostructure

Abstract

In this article, the heterostructure of ZnO particles on single-crystal CdS nanowires (ZnO@CdS) has been successfully synthesized via a facile two-step solvothermal process. The appealing application of the ZnO@CdS heterostructure as visible-light photodetector (PD) is presented. Photocurrent illuminated with light (shorter than 510 nm) to dark-current ratio of structurally-optimized ZnO@CdS nanomaterials based photon detector was enhanced significantly compared to the value of the pristine CdS nanowires based one. The corresponding mechanism for the phenomenon was discussed. Additionally, measurements of time resolved responses were conducted. The ZnO@CdS heterostructure based device kept a fast rise (5 ms) and decay (10 ms) speed to irradiation. This work demonstrates a promising application of ZnO@CdS heterostructure based visible-light detectors with high photocurrent/dark-current ratio, ultrafast time response and very good stability.