Enhanced electrochromic properties of a TiO2 nanowire array via decoration with anatase nanoparticles

Abstract

Construction of a micro-/nanostructured TiO₂ film has been considered to be an important way to enhance the electrochemical properties and electrochromic performance of the material. Herein, we investigated the electrochromic properties of a nanocomposite TiO₂ film prepared by decorating rutile a TiO₂ nanowire (TiO₂ NW) array with anatase TiO₂ nanoparticles (TiO₂ NPs) via a facile two-step synthesis method. Owing to its large active surface area and high transparency, the TiO₂ NW–NP composite film supported a greater number of sites for Li⁺ ion intercalation and extraction. As a result, the TiO₂ NW–NP film displayed higher optical contrast, coloration efficiency and transient current density compared with NW and NP films, demonstrating that enhanced electrochromic properties could be achieved using the NW–NP composite structure.