Nb-doped TiO2 mesoporous films with improved electrochemical and electrochromic energy storage performance

The development of high-quality cathode material is of important value to the research of bifunctional electrochromic energy storage device. Therefore, Nb-doped TiO 2 mesoporous film as the high-performance cathode was prepared via a facile sol-gel technology successfully. The Nb doping content has great effects on the crystallinity and chemical state of TiO 2 films. Compared to the pure TiO 2 film, the optimum Nb-doped TiO 2 film exhibits the excellent optical-electrochemical performance including highest large-rate capability, largest specific capacity (62.4 mAh/g), short switching time (3.4 s/4.5 s) and large transmittance modulation (50.7%). These data indicate that Nb-doped TiO 2 mesoporous films possess the important application prospect.