Preparation and Study of Nano Silica Antireflective Film by Sol–Gel

The refractive index of nano silica film was lower than that of glass substrate, which could improve the transmittance and the utilization ratio of sunlight. In this paper, SiO2 sol was prepared by Sol–Gel technology, and nano SiO2 antireflection film was fabricated on photovoltaic glass via dip-coating method. The properties of the film were characterized by FESEM, spectral transmittance meter and ellipsometer. The FESEM observation showed that the surface of silica antireflective film was smooth and the thickness was 90–100 nm. The transmittance results indicated that the transmittance of SiO2 antireflection film was 2.0–2.8% higher than that of glass substrate. The refractive index results suggested that the refractive index decreased to 1.32–1.35 after coating with SiO2 antireflection film. The weathering treatment result demonstrated that the weather resistance of SiO2 antireflection film was good.