Electrochromic ultra-thin films based on cerium polyoxometalate

Ultra-thin multilayer films consisting of polyoxotungsceriumate cluster K17[CeIII(P2W17O61)2]·30H2O [Ce(P2W17)2] and polyallylamine hydrochloride were fabricated on quartz and ITO substrates by a layer-by-layer self-assembly method. The multilayer films were characterized by UV-vis spectra, cyclic voltammetry (CV) and chronoamperometric (CA) measurement. Compared with other polyoxometalates, the electrochromic film exhibits suitable response times, low operation potentials, high optical contrast and thermal stability, which provide valuable information for exploring the possibility of application to polyoxometalate-based electrochromic materials.