Superior self-cleaning glass through hydrophobic and superhydrophilic coating for outdoor applications

The wettability of the coating surface is strongly exhibit as practical approach for self-cleaning purposes. In this paper, a transparent hydrophobic nano-CaCO3/ modified PDMS coating with hydrophobic properties and superhydrophilic nano-TiO2 coating with good self-cleaning properties have been successfully developed for glass substrate application. The coating was applied onto glass plates using sponges and tested against water contact angle (WCA) measurement. The hydrophobic coating achieves the WCA as high as 117±2° and superhydrophilic coating achieves water contact angle as low as 4.9±0.5°. For superhydrophilic surface, the applied dirt liquids tend to spread across the coating surface. For hydrophobic coating, the applied dirt liquids are completely removed from the coating surface. The prepared-coating also exhibits an excellent anti-fogging and anti-water streak behavior due to the absence of water-streaks and water-droplets are appeared on both coated glass surfaces after impacting to water-spraying and fog testing. In conclusion, this hydrophobic coating and superhydrophilic coating will be highly practical for outdoor applications of photovoltaic panel.