Metal-Oxide modified TiO2 nanostructured thin films for self-cleaning application in Photovoltaics /

Abstract

Solar energy is still one of the appealing energy sources despite its variable availability based on the time and location. Keeping surfaces clean and preventing the buildup of dust and other pollutants is crucial for improving the effectiveness of solar energy conversion devices, such as photovoltaic panels. Self-cleaning surfaces have achieved success in the environmental and energy sectors recently. These surfaces are employed, in particular, in the solar energy sector to prevent the buildup of dirt on photovoltaic (PV) modules. In this study, optically transparent, hydrophilic Silica (SiO2) modified Titania (TiO2) nanofibrous thin films have been synthesized on glass substrates via using electrospinning technique for self-cleaning application in a solar cell. The coatings were prepared by varying the TiO2-SiO2 ratio as (3:1, 1:1, 1:3). TiO2-SiO2 formulated ratio (1:1) outperformed in comparison to other formulations and was found to have a crystalline nature with randomly orientated network of fibers having diameter in the range 88-95nm. FTIR spectroscopy confirms complete evaporation of polyvinylpyrrolidone (PVP) from temperature annealed sample. The electrospun TiO2-SiO2 (1:1) nanofibers showed hydrophilic nature with water contact angle (WCA) of 11.3°. The Soiling study was performed under different tilt angles of 0°, 33.4° and 60°. Upon soiling the coating showed >16% enhancement in optical transmittance than the glass substrate. Soiling density decreased up to 38.9%, and to 64.9% in comparison to uncoated substrate that showed 9.08%, and 22.2% and the photovoltaic (PV) efficiency was improved by 0.8% and 1% for tilt angles of 33.4° and 60° respectively.