Design of core-shell SiO2 nanoparticles to create anti-reflection and anti-fouling coatings for solar cells

Amphiphobic coatings with the anti-reflective property offer a promising strategy to mitigate the degradation of photovoltaic conversion efficiency in solar cells caused by fouling and reflection of incident light. Despite advancements in developing transparent and liquid-repellent coatings, achieving integration of both properties still poses a significant challenge. In this work, a unique nanostructure coating with extremely low roughness and surface energy is constructed by integrating fluorinated cluster core-shell structured silicon sols (BASSF) into a self-made silicon precursor (SP) using a template-free two-step base/acid-catalyzed reaction. The exceptional anti-fouling performance of the S-P@BASSF coating is a result of the chemical inertness of the polymer and the unique structure of the sol-gel particles. This innovative approach provides a potential solution for fabricating high-performance coatings and materials. The coating is capable of recovering to 97 % of its initial efficiency swiftly, even after severe dust contamination. The coating exhibits remarkable anti-reflective property due to the combination of sol particles with varying refractive indices. The coating also displays high weathering resistance, maintaining contact angles with water (≥105°) and diiodomethane (≥85°) even after prolonged exposure to UV lamps, high temperature and high humidity weather. The results obtained in this study show that nanocomposite coatings via the preparation of smooth, high refractive index and low reflectivity have great potential for outdoor applications such as energy harvesting and optical instruments under wet conditions.