Optical and Photodetection Properties of ZnO Nanoparticles Recovered from Zn Dross

In this study, we report the synthesis of ZnO nanoparticles from Zn dross via hydrometallurgical method by using acetic acid as a leaching agent. D205 dye molecules were then adsorbed onto Zn dross originated ZnO nanoparticle film. The optical absorption confirms the photosensitization of the synthesized ZnO nanoparticles with dye. The photoluminescence spectra reveal the excitonic- and defect-related emission of ZnO nanoparticles. Compared to ZnO nanoparticles only, the longer emission lifetime of ZnO nanoparticles with adsorbed dye indicates the transfer of photoexcited electrons from dye to the ZnO nanoparticles. Furthermore, photodetection characterization of ZnO film show the enhanced current density with the presence of dye under simulated solar illumination, while that measured at dark is similar in both films with and without dye. This result confirms the potentiality of Zn dross to be recycled into valuable ZnO nanoparticles particularly for the applications in the visible light region, especially for sensing.