Array of ZnO nanoparticle-sensitized ZnO nanorods for UV photodetection

Vertically aligned ZnO nanorod (NR) arrays have been successfully synthesized on ITO-glass substrate by hydrothermal growth. Chemical bath deposition method was used to deposit ZnO nanoparticles (NPs) onto the ZnO NRs. These structures were applied in fabricating ZnO NPs sensitized ultraviolet (UV) photodetectors (PDs). Incorporation of ZnO NPs onto ZnO NRs results in distinct improvement of optical properties of ZnO NRs, i.e., significant enhancement of emission as well as effective suppression of defects emission in ZnO. Furthermore, there is a noticeable blue-shift in absorption spectra compared with that of ZnO NRs structure. I–V characteristics show that the sensitized structure improved photocurrent almost twice that of unsensitized ZnO NRs. Consequently, these findings may open new opportunities for the integration of different ZnO nanostructures for application in UV region particularly fabrication of UV PDs.