Enhanced electrochromic performance of a vanadium-substituted tungstophosphate based on composite film by incorporation of cadmium sulfide nanoparticles

Abstract

A composite film consisting of vanadium-substituted tungstophosphate α2-K7P2VW17O62·18H2O (P2W17V) and cadmium sulfide nanoparticles (CdS) was fabricated on quartz, silicon and indium oxide substrates by layer-by-layer self-assembly method. The composite film {PEI/[P2W17V/PEI–CdS]n/P2W17V} was characterized by UV–visible spectra, cyclic voltammetry, chronoamperometry, atomic force microscopy, scanning electron microscope and X-ray photoelectron spectra. Visually optical contrast from light yellow to dark goldenrod can be seen for the composite film during the potential scanning between 0 and −1.1V. The 30 bilayers composite film displayed the optical contrast of 59.8% and coloration efficiency of 38.29cm2C−1 at 543nm which were remarkably enhanced in comparison with the CdS-free film. Therefore, the CdS should be the attractive active component to improve performance of electrochromic materials.