Water-repellent glass coated with SiO 2 -TiO 2 -methyltrimethoxysilane through sol-gel coating

Abstract

A hydrophobic coating for glass substrates was developed using Si 2 , TiO 2 , and methyltrimethoxysilane (MTMS) to achieve low surface energy and a rough surface. The coating process was conducted using a sol-gel method and layer by layer deposition. The effect of Si 2 , Ti 2 , and MTMS on the hydrophobicity and transparency of the coating were evaluated using contact angle and optical transmittance measurements, respectively. The transparency was found to decrease with higher moles of Si 2 , Ti 2 , and MTMS; the water contact angle initially increased with increasing addition of these reagents, but then declined above the optimum conditions. The optimum conditions were determined to be at approximately 0.075, 0.030, and 0.002 mol of Si 2 , Ti 2 , and MTMS, respectively. The resulting water contact angle was 115.56 ± 1.01°. Si 2 and Ti 2 provided a synergistic effect to improve the roughness surface, as shown in the AFM data. The glass coated using Si 2 -Ti 2 -MTMS exhibited higher hardness values than bare glass.