Juntima Chungsiriporn, Prukraya Pongyeela and Nirana Chairerk

DOI: 10.14456/sjst-psu.2020.118

pp. 923 - 927

Abstract

Thin film sol-gel coatings on glass substrates for use in solar cells were studied. The precursor solution was made of
tetraethoxyorthosilicate (TEOS 2.0-6.0% v/v) using hexadecyltrimethoxysilane (HDTMS 0.1-1.5% v/v) as hydrophobic modifier
in the presence of NH₄OH (0.05-1.0% v/v) as catalyst. Dip-coating was applied to glass and studied for the effects of sol
preparation on water-contact angle, transmittance, and resistance to outdoor exposure of the coating. The results showed TEOS,
HDTMS and NH4OH contents at 6.0, 1.0 and 1.0 vol.%, respectively, as optimal. Superhydrophobicity with a water-contact
angle of 150.69^o can be achieved with high transmittance and self-cleaning properties. The morphology and surface roughness
were characterized by AFM and showed aggregates of silica particles in combination with the inherent microscale roughness of
glass. The stable voltage of solar cells having a coatings of this type (dip-coating in sol-gel with NH₄OH catalyst) meets the
industrial requirements with potential for outdoor applications.

Keywords

• sol-gel
• solar cell
• nanotechnology
• superhydrophobic
• dip-coating