Study of wettability, structural and optical properties of zinc oxide nanorod array coated with gold thin layer

Abstract

Zinc Oxide (ZnO) has gained much attention in the modern technology world due to their varied uses. ZnO nanorod array coated with gold thin layer especially seem to provide much more benefits outweighed to just ZnO nanorod itself. However, to our best knowledge, ZnO nanorod array coated with gold thin layer have not been thoroughly researched in their reversible wettability and optical properties relating to self cleaning applications. In this study, hydrothermally grown ZnO nanorod array were prepared and subsequently coated with thin gold layers. The samples were characterized based on wettability, morphological and optical properties mainly using, Water contact angle Goniometer, Transmission Electron Microscopy (TEM), Roughness Testing and Ultraviolet-visible (UV-vis) spectroscopy. The obtained experimental data revealed that the ZnO nanorod array coated with gold thin layers possessed reversible wettability properties upon application of Ultraviolet (UV) light exposure and reversed upon placing the samples into a dark box. The optical properties of the samples showed great improvement especially with a thicker coating of gold. This property is beneficial for solar cell applications and also for self-cleaning uses where absorption will bring about improvement in reversal wettability properties.