A potential method to induce hydrophobicity on glass surface while retaining its anti-reflective abilities

Abstract

Fabrication of anti-reflective and hydrophobic glass surfaces has been an active area of research. It has been reported that most of the coatings developing methods produces fragile and thin coatings which consequently have limited practical usage because of their abrasion-sensitivity. However, with thicker coatings, transparency of glass gets compromised, rendering it inoperable to be used in applications requiring transparency. To overcome the problem there is a need to have a solution that can practically produce glass substrates having hydrophobic properties without significant loss in transmittance, making them useful in anti-reflective hydrophobic applications. The presented work focuses on utilizing the effects of surface roughness and surface chemistry on commercial grade glass substrates to produce robust hydrophobic surfaces without appreciable compromise on transmittance. Metal Assisted Chemical Etching (MACE) was used to develop controlled structured surface roughness on the glass substrate whereas the surface chemistry was modified via silane treatment. The results demonstrated surface roughness and surface chemistry are both equivalently important to achieve an optimum surface having hydrophobic properties without any major transmittance lost. Successful implementation of the silver (Ag) particle assisted MACE process and chemistry modification of the glass surface resulted in contact angles above 100° with nearly 2–3% transmission lost in reference to the transmittance of parent glass substrates.