Preparation of hydrophobic SiO2/PTFE sol and antireflective coatings for solar glass cover

Reflection from the surface of solar panels is important factor to limit the efficiency of all of photovoltaic devices. Antireflective coatings (ARCs) can significantly reduce surface reflections and improve photovoltaic module efficiency. But, ARCs on solar glass, used in photovoltaic (PV) modules, usually located in terrible environments, which demands that ARCs must hinder moisture penetration, abrasion damage, and dirt accumulation. In this study, the films with highly antireflective properties that maintains a high durability and hydrophobic were prepared through a simple sol-gel method by using PTFE (Polytetrafluoroethylene) modified. The average transmittance of glass with ARCs was 97.86 % at 400-800 nm, which was an increase of 7.86 % compared to the bare glass. X-ray Diffraction (XRD), Fourier Transform Infrared spectrometer (FT-IR), field emission scanning electron microscope (FE-SEM), ellipsometer, atomic force microscope (AFM), UV-vis-NIR spectrophotometer and water contact angle analyzer were used to measure the surface composition, morphology, refractive index, surface roughness, optical and hydrophilic properties of the coatings. The results revealed that the deposition of PTFE modified SiO2 coating on the glass substrate had a significant enhance on the antireflection, abrasion-resistance and hydrophobic property.