Structural and optical behavior of (WO₃)_0.90(V₂O₅)_0.10 thin films

Among the transition metal oxides WO₃ appears to be the best electrochromic material for smart window applications. Neutral coloring can be achieved by modified WO₃ films using V₂O₅. In the present work, V₂O₅ is mixed with WO₃ and ground in a ball milling machine. X-ray diffraction studies are carried out for the powder sample ground for different duration of time. Sputtering target made from the pressed powder is sintered to get homogeneity. V₂O₅ doped WO₃ thin films are deposited by varying the parameters such as RF power and the substrate temperature and other sputtering parameters are kept at constant. As-deposited films are amorphous for all the film deposition parameters. Room temperature photoluminescence (PL) properties of the deposited films are studied. They revealed the presence of emission peak centered at 375 nm when excited at 275 nm. (author)