ELECTROCHROMIC PROPERTIES OF MULTILAYER FILM BASED ON POLYOXOMETALATE AND CDS NANOPARTICLES

Jia-Ning Tan, Ning Yang, Ru-Fan Han, Su-Yang Feng, Yan-Yan Yang, Xiao-shu Qu, Hui Feng

ABSTRACT:The electrochromic films of PEI/[P5W30/PEI]20 and PEI/[P5W30/CdS]20 were composed of the polyethyleneimine (PEI), polyoxometalate cluster K12.5Na1.5[NaP5W30O110]· 15H2O (P5W30) and cadmium sulfide (CdS) nanoparticles. They were fabricated on fluorine-doped tin oxide (FTO) glass and quartz by the layer-by-layer self-assembly method, respectively. The composition and growth process of the two films were characterized by ultraviolet-visible spectra. The electrochemical properties of the films were investigated by cyclic voltammetry and a double-potential step chronoamperometric experiment. The PEI/[P5W30/CdS]20 film reveals higher electrochromic performance than the PEI/[P5W30/PEI]20 film, whose optical contrast is up to 51.04 %, increase by 68.12 %, and shows the response time for coloration 2.58 s (bleaching 1.96 s). Furthermore, the PEI/[P5W30/CdS]20 film has a coloration efficiency of 127.18 cm2/C, improve of 133.92 %. Obviously, the electrochromic performance of composite film has been enhanced by the addition of CdS nanoparticles.

Keywords:Electrochromic, Polyoxometalate, layer-by-layer self-assembly, CdS nanoparticles