Synthesis of copper doped Zinc oxide nanowires with enhanced ultraviolet photoresponse behavior

Abstract

This work mainly focused on the synthesis of copper doped zinc oxide nanowires by hydrothermal method, their characterization and their ultraviolet (UV) light sensing response at room temperature. The structural and morphological characterization was carried out using X-ray diffraction and scanning electron microscopy. Enhanced ultraviolet (UV) photodetection property has been achieved for a dopant concentration of 2.5wt% and 5wt% showing UV photosensitivity values (photo-to-dark current ratio) of around 800 and 1800, respectively. This is an order of magnitude higher than the undoped ZnO nanowires. High photocurrent gain is attributed to the trapping of carriers under dark and detrapping them under UV illumination by Cu-related defects. Enhancement in photosensitivity indicates that Cu-doped ZnO nanowires are promising candidates for UV photodetection applications.