Testing the Durability of Fluorine-Free Hydrophobic Coatings vs Porous Silica

Current porous SiO
2
anti-reflective coatings used on solar modules have recently been found to be susceptible to mechanical abrasion and environmental degradation. A fluorine-free polymeric anti-soiling coating is tested as an alternative coating to porous SiO
2
. Two hydrophobic coatings, porous SiO
2
, and a glass control were subjected to a linear abrasion test under 5N of force for 50 cycles. The porous SiO
2
demonstrated higher initial optical transmittance and reflectance but degraded by -0.7 T% and +1.6 R% after 50 cycles of abrasion. The hydrophobic coating with SiO
2
nanoparticles demonstrated resistant to abrasion with 0 T% and +0.1 R % increase, outperforming the control glass. The nanoparticle filled hydrophobic coating also retained its hydrophobic properties after abrasion with a WCA of 96° which is beneficial in their role as an anti-soiling coating.