Investigation on the Properties and Mechanism of W-Doped TiO₂ Electrochromic Films Deposited by Cosputtering

Recently, there has been increasing interest in the application of TiO2 in electrochromic devices. However, there is still a lack of relevant research on the development of convenient preparation methods for TiO2 electrochromic devices, enhancing their performance and providing a comprehensive explanation for the discoloration phenomenon. In this paper, W-doped TiO2 thin films were prepared by DC magnetron and MF magnetron cosputtering. The electrochromic properties of W-doped TiO2 thin films are excellent (the light modulation amplitude at 550 nm reaches 68%). The electrochromic mechanism was studied by combining experimental and theoretical calculations. Finally, a quasi-solid-state electrochromic device was designed based on the single-layer film, which has high optical modulation, fast spectral response time, and good electrochemical stability (no loss of optical modulation after 500 cycles).