Fabricating and investigating high photoresponse UV photodetector based on Ni-doped ZnO nanostructures

Abstract

In this study, pure (ZnO) and Ni-doped ZnO (ZnO: Ni) nanostructures with different concentrations of Ni (93:7, 95:5, 97:3 weight ratios) were successfully prepared by using thermal decomposition method. The structural, morphological, optical and optoelectronic properties of ZnO and ZnO: Ni were evaluated by XRD, FE-SEM, UV–Vis, I–V and I–t measurements. XRD results confirmed that Ni was successfully incorporated into the ZnO structure because all the samples had a single-phase hexagonal structure. Upon the incorporation of Ni into ZnO, the shape of the nanostructures changed from rod to spherical-like. UV–visible spectra the doped samples showed a blue shift compared to the pure sample. The UV photodetector based on ZnO and ZnO: Ni nanostructures with metal–semiconductor–metal (MSM) configuration structure was fabricated for the UV photodetector. The UV photodetector based on ZnO: Ni samples showed excellent photoresponse time compared to pure ZnO. The results indicated the sample doped with 7% Ni offered the highest response rate (the rise and decay time were 0.5 s and 2 s, respectively).