Rapidly synthesized ZnOnanowires by ultraviolet decomposition process in ambient air for flexible photodetector

Abstract

We are the first group to use a simple direct ultraviolet light (UV, λ = 365 nm, I = 76 mW cm⁻²) in a decomposition process to fabricate ZnO nanowires on a flexible substrate using a zinc acetylacetonate hydrate precursor in ambient air. ZnO nanocrystal (or nanowire) production only requires three to ten minutes. A field emission scanning electron microscopy (FESEM) image reveals a high aspect ratio of the ZnO nanowires, which are grown on a substrate with a diameter of ∼50–100 nm, and a length of up to several hundred microns. High resolution transmission electron microscopy (HRTEM) images reveal that the nanowires consist of many single crystalline ZnO nanoparticles that grow along the c axis, which suggests an oriented attachment process. A potential application for flexible UV photodetectors was investigated using a UV lamp (λ = 365 nm, I = 2.34 mW cm⁻²). A significant ratio of photocurrent to dark current—around 11 300%—was achieved.