Study of the Wettability of ZnO Nanofilms

Al-doped and un-doped ZnO thin films deposited on quartz substrate by the nebulized spray pyrolysis method were studied to investigate the wettability of the surface. The main objective of the present study was to investigate the wettability of ZnO thin film by changing the concentration of Al doping. Microstructure and water contact angles of the films were measured by SEM and contact angle goniometer. SEM studies revealed that the grain size within the film increases with the doping concentration. The contact angles were studied to see the effect of aluminum doping on the hydrophilicity of the film. ZnO films were found to be hydrophobic in nature. A good correlation was observed between the SEM micrographs and contact angle results. The nature of the film was found to change from hydrophobic to hydrophilic after the treatment in low pressure DC glow discharge plasma, which, however, was reversible with the storage time.