Characteristics of oil impregnated hydrophobic glass surfaces in relation to self-cleaning of environmental dust particles

Maintaining the high performance of photovoltaic devices requires regular cleaning of panel surfaces because of the environmental dust settlements in harsh weather conditions. Self-cleaning characteristics of such surfaces are vital for the cost effective operations. In the present study, a new fabrication approach is introduced towards self-cleaning applications of optically transparent glasses. In the fabrication process, self-assembly monolayer of silane was coated on the silica nanoparticle layer, prior to oil impregnation, to improve oil hydrodynamic stability of the oil film on the surface. The static water contact angle, sliding angle and average optical transmittance of the resulting surfaces are measured. The scanning electron microscope and atomic force microscope are used to reveal the hierarchical morphology of the surface. Dust cleaning tests are performed to evaluate the self-cleaning characteristics of the surfaces. The findings revealed that the water droplets can be effectively used to remove almost all of the dust particles from the surfaces. Oil impregnation improved the optical transmittance of the treated hydrophobic glass surface. •Functionalized silica nanoparticles resulted in hierarchical surface texture.•Textured surface improves surface hydrophobicity significantly.•Oil impregnation of textured surface reduces apparent contact angle.•Oil impregnation improves optical transmittance of textured surface.