Study of the mechanism of the variable emissivity infrared electrochromic device based on polyaniline conducting polymer

Variable emissivity infrared electrochromic device based on polyaniline(PANI) conducting polymer has been prepared and the mechanism of IR electrochromic device has been investigated by in situ technology. Results show that the device has good electrochromism in the mid-infrared (mid-IR) ranges (3–5 μm, 8–12 μm). IR reflectance and transmittance measurements of the PANI/polyethylene (PE) composite film under different potentials show that the transmittance change of the PANI film under different potentials is the main affecting factor of the emissivity change of the device. In-situ Fourier transform infrared attenuated total reflection (FTIR-ATR) measurement of the device demonstrates that almost all peaks of the PANI film at 0.8 V have red-shifted compared to the peaks of the film at −0.8 V. A conversion of quinoid ring to benzenoid ring in the PANI film happens when the potentials changes from 0.8 V to −0.8 V and the doping degree of the PANI film at 0.8 V is deeper than that of the film at −0.8 V.