Enhanced Electrochromic Performances of Polyaniline-Coated Rod-Like ATO/TiO2Nanocomposites

The organic-inorganic nanocomposites and their thin films of polyaniline (PANI) coated rod-like antimony-doped SnO 2 /TiO 2 (ATO/TiO 2 ) inclusions at different loadings are prepared using in situ chemical oxidative polymerization. The electrochromic performances of the PANI coated ATO/TiO 2 nanorod (ATO/TiO 2 @PANI) composite films are investigated in 0.25 M HCl electrolyte solution. The hybrid film of PANI with inclusion 5% ATO/TiO 2 loadings shows remarkable enhancement of film forming properties and electrochromic properties. A significant optical contrast ratio (29.6% at 700 nm), fast response speed (1.4 s for bleaching, 1.7s for coloring) and excellent cycling stability (over 500 cycles) are achieved for the hybrid nanorod film containing 5%ATO/TiO 2 inclusions. The improved electrochromic properties are mainly attributed to the core/shell structure, formation of the donor-acceptor system, and the porous space among the nanorods, which can reduce the oxidation potential, make the ion diffusion easier and provide larger surface area for charge-transfer reactions.