Triple layer tungsten trioxide, graphene, and polyaniline composite films for combined energy storage and electrochromic applications

Abstract

Different polyaniline (PANI)-based hybrid films were successfully prepared by electro-polymerizing aniline monomers onto pre-spin-coated indium tin oxide (ITO) glass slides with WO3, graphene, or WO3/graphene films. Comparing with pristine PANI, the shifts of the characteristic peaks of PANI-based nanocomposites in UV-visible absorption spectra (UV-vis) and Fourier transform infrared spectroscopy (FT-IR) indicate the chemical interaction between the PANI matrix and the nanofillers, which is also confirmed by the scanning electron microscope (SEM) images. Corresponding coloration efficiencies were obtained for the WO3/PANI (40.42 cm2 C-1), graphene/PANI (78.64 cm2 C-1), and WO3/graphene/PANI (67.47 cm2 C-1) films, higher than that of the pristine PANI film (29.4 cm2 C-1), suggesting positive effects of the introduced nanofillers on the electrochromic performance. The areal capacitances of the films were observed to increase following the order as bare WO3 < pristine PANI