Constructed TiO₂/NiO Core/Shell Nanorod Array for Efficient Electrochromic Application

A TiO 2 /NiO core/shell nanorod array film is prepared by the combination of hydrothermal and chemical-bath deposition. Compared to the NiO nanoflake film, the TiO 2 /NiO core/shell nanorod array exhibits better electrochromism with reversible color changes bewteen transparency and dark brown, shows larger optical modulation (83%), higher coloration efficiency (60.6 cm 2 C 1– ) and better cycling performance. The enhancement of electrochromic performances is attributed to the synergetic contribution from the single crystalline TiO 2 nanorod core and the ultrathin NiO nanoflake shell, as well as the ordered array geometry, which can all offer direct electrical pathways for electrons and increase the electron transport rate.