Sol-Gel preparation and wetting behaviour analysis of hydrophobic Zirconium based nano-coating: Implications for solar panel coating

Abstract

Hydrophobic coatings basically decrease the wettability of surface due to the presence of nanostructures on it. In this research work, nanozirconia sol was prepared by the sol-gel method and further hydrophobically modified using the hexamethyldisilazane (HMDS). Prepared sol was coated on the glass substrate and then analysed for its wetting behaviour. Three samples with different HMDS ratios mixed to Zirconia sol were coated, and analysed for surface morphological parameters through the atomic force microscopy and field emission scanning electron microscopy techniques. The wetting behaviour was analysed by studying the water contact angle and surface free energy of the samples. Here the transmittance was measured by transmittance metre at regular intervals for 30 days. Functional group determination was done by Fourier transform infrared spectrometer that confirmed the formation of Zirconium nanoparticles. Maximum contact angle of 101.2° was observed that showcased the hydrophobic properties. Hydrophobic coating was then successfully prepared, and sample with 2:1 ratio of Zirconium nanoparticles and HMDS showed the best hydrophobic nature amongst all the coatings prepared in this investigation.