Synthesis and characterization of Photochromic inkless coating based on WO3-Titania nanocomposite under sun light and solar simulation condition

A highly efficient and surfactant free hydrothermal method is adopted to synthesis tungsten trioxide (WO3) modified Titania (TiO2) composite for direct visible light photochromic applications. The physico chemical characterization of anatase phase formation confirmed by X-Ray diffraction (XRD) and Raman Spectroscopy. The different weight percent amount of tungsten trioxide incorporated into TiO2 nanocomposite have been studied for coloration and bleaching property under in the presence and absence of visible light irradiation. The as prepared composite form of WO3-Titania shows efficient and stable cycle performance up to 15 cycles at various time intervals. The Transmission electron microscopy (TEM), Scanning electron microscopy (SEM) reveals the largely consisting of square and small circular like particles formation and each square and spherical shapes. The photochromic response of the materials increases in the order of WO3/TiO2(0.5:1)> WO3/TiO2 (1:1)> >WO3/TiO2-2(1:2) and in the case of WO3/TiO2-3(1:3) and WO3/TiO2-(1:4) are consumed little more time for coloration and bleaching process. The cycle stability and color transformation have also been studied for efficient WO3/TiO2 (WT-2) sample under direct sun light and in controlled solar simulator reaction condition.