Durable Superhydrophobic Low-Reflectance Coatings for Next-Generation Photovoltaics: Optical and Environmental Performance of Fluoropolymer Laminates

This study presents a new approach to PV surface protection using transparent fluoropolymer laminates— specifically fluorinated ethylene propylene (FEP) and ethylene tetrafluoroethylene (ETFE) hot-pressed onto cover glass substrates. These coatings demonstrate multifunctional anti-reflective (AR) and anti-soiling (AS) properties, including water contact angles exceeding 140°, weighted average reflectance (WAR) as low as 5.93%, and sustained performance under 1000 hours of UV exposure and 1000 cycles of mechanical abrasion. Surface analysis (XPS, FTIR, SEM) confirmed chemical stability and minimal degradation, suggesting that FEP laminates in particular offer a robust, scalable alternative to fragile porous silica-based coatings for use in arid, high-soiling environments.