Superhydrophilic Self-Cleaning Coatings Based on Zwitterionic Brush-Silica with High Transmittance and Durability for Photovoltaic Panels

Photovoltaic (PV) panels are critical for solar energy utilization and global carbon neutrality. Nonetheless, their efficiency is compromised by surface contamination and fogging, which attenuate light transmission and energy output. Superhydrophilic self-cleaning coatings present a compelling strategy, yet developing coatings with comprehensive antifouling capabilities, high visible light transmittance (VLT), and sustained environmental durability remains a significant scientific and engineering challenge. Here, we report a highly integrated zwitterionic brush-silica hybrid (ZBSH) coating, rationally designed via a ternary synergistic strategy. A zwitterionic brush resin named PSKA is synthesized via molecular design and free-radical polymerization, achieving intrinsic superhydrophilicity. The integration of silica sol forms a nanostructured continuous inorganic network, simultaneously enhancing both superhydrophilicity and VLT. The diamine-terminated oligomer poly(propylene glycol) bis (2-aminopropylether) (D230) is employed as a bridge molecule and cross-linker, establishing covalent networks with the carboxyl groups of PSKA. The optimized ZBSH coating exhibits comprehensive self-cleaning properties, achieving 82% recovery in PV panel efficiency following contamination. Notably, the coating maintains superhydrophilic properties under stringent durability assessments and outperforms most products of the same type. These findings offer novel perspectives and practical insights for advancing self-cleaning coating technologies in PV panels.