The Impact of Simulated Direct Sun Radiation on the Thermal and Optical Performance of Cellular Glass Coated with WO3 Based Painting

The thermal and optical properties of commercial glass foam covered with a functional coating designed for exterior and environmental applications were investigated. The coating was prepared using WO₃ a photocatalytic material - as a pigment and acrylic resin - as a binder. The temperature variation at different depth points and on the surface of the glass foam, before and after the application of 1-4 layers of WO₃, during the exposure to the simulated sunlight, was monitored. Physical and chemical characterization - RGB and reflectance measurements were conducted for the glass foam surface before and after being covered with WO₃-based coating and FT-IR, Raman and EDAX spectroscopy, X-ray diffraction, and 3D laser scanning microscopy were used for the as-prepared WO₃ powder, the glass foam, and the applied layers of WO₃ based coating. The change in WO₃-based coating spectral properties under external stimuli was emphasized and correlated with the optical and structural properties of the WO₃ powder. Surface roughness, color, and spectral reflectance were improved after multiple layers of the coating.

Keywords: WO₃ pigment; Color change; Glass foam; Direct simulated solar irradiation; Spectral reflectance