Quantum-sized TiO2 particles as highly stable super-hydrophilic and self-cleaning antisoiling coating for photovoltaic application

Soiling influences power generation and reduces the power conversion efficiency of solar energy conversion devices. In this regard, we successfully synthesized highly photocatalytic active quantum-size TiO2 particles with an average particle size of 6 nm and utilized the same to develop a highly transparent antisoiling coating. The material is characterized by small angle X-ray scattering, and the average particle size is found to be 6 nm. Automated spray coating technique was employed for the development of antisoiling coating on PV cover glass and minimodule. The coating exhibited exceptional weather stability (IEC 61646) for over 1500 h, excellent photoinduced superhydrophilicity in a span of 60 mins. Photocatalytic activity of the antisoiling coating is studied by analyzing the degradation of methylene blue and 4-chlorophenol. Promising antisoiling performance was observed from the antisoiling coated PV module as it resulted in 2.5% lower soiling loss compared to that of not-coated minimodules. The coatings exhibited excellent mechanical stability and Omni transparency.