Facile Fabrication of Transparent Hydrophobic Spectral Converting Thin Film of Cyclic Silica-Silane Structure

There is a growing demand for advanced coatings with remarkable physical properties such as high transparency, water resistance, spectrum conversion, and dust repellence, which can be used in a variety of applications. In this study, we built thin films using silicon quantum dots and a silane-based material composite, resulting in a unique mix of hydrophobicity, self-cleaning and the ability to convert ultraviolet (UV) to visible spectrum. The use of silicon quantum dots in the film results in spectrum conversion from UV to visible wavelengths, taking advantage of their broad UV absorption and concurrent visible light emission. Concurrently, a silica-silane based layer of tetraethyl orthosilicate, N, N dimethyl amino propyl trimethoxy silane, and 3-chloro-propyl trimethoxy silane is integrated, imparting not only water resistance but also dust resistance. The challenging synthesis chemistry exemplifies the several stages required to create a spectral-converting hydrophobic layer. Given its inherent transparency, coupled with UV-to-visible spectrum conversion capabilities, this novel layered structure have a potential in outer coating of solar photovoltaic systems and various outdoor glass applications.