Hydrogen bonding of graphene/polyaniline composites film for solid electrochromic devices

Hydrogen bonding of graphene (SG) was prepared by self-assembly method. Polyaniline (PANI)-based composites films with SG were prepared by using in electrochemistry polymerization, which made solid-state electrochromic device (SG/PANI) assembled. Scanning electron microscopy (SEM), X-ray diffraction techniques (XRD), Fourier transform infrared (FT-IR), transmission electron microscopy (TEM), thermogravimetric analysis (TGA), UV-vis absorption spectra and cyclic voltammetry (CV) measurements were used to characterize the SG/PANI film and solid-state electrochromic device. SEM and TEM showed a good and uniform dispersion of the SG in the PANI matrix. The surface of the films contains hydrogen functional groups, which have been characterized by FT-IR. The different content of SG played a pivotal role in the electron transfer and regulated the conductivity of the films. UV-vis absorption spectra and CV measurements showed the SG/PANI-5 changed to the range of green to black and good electrochromic cycle characteristics, switching color is for 5.23 s, and bleaching for 1.04 s.