Durable superhydrophilic and antireflective coating for high-performance anti-dust photovoltaic systems

Antireflection coatings have received extensive attention due to their unique ability to reduce the reflection losses of incident light in photovoltaic (PV) systems. In this study, we report a hybrid silica sol coating fabricated via a simple and cost-effective base/acid-catalyzed two-step sol–gel method. The prepared coating exhibits these main properties: high transmittance, superhydrophilic, and anti-dust effect. Experimental conditions to achieve high transmittance were systematically optimized, such as aging time of the base-catalyzed silica sol and dip-coating speed. A transmittance improvement of about 6.35% compared to the bare glass substrate was then obtained. The morphology and film structure were also characterized. The coatings have a closed and dense structure which, combined with their superhydrophilicity, endowed them with excellent anti-dust performance, as well as high mechanical properties, with a pencil hardness of 4H. Furthermore, the coating showed great resistance to high temperature and high humidity as well as high stability to long-time outdoor exposure. The results suggest the good reliability of the prepared coatings for PV solar glass application.