Enhanced electrochemical performance of hydrogen-bonded graphene/polyaniline for electrochromo-supercapacitor

This study focuses on a supercapacitor with displaying variations in color schemes depending on the level of energy storage. In this paper, hydrogen-bonded graphene/polyaniline (HbG/PANI) was successfully synthesized by electrochemical polymerization method. The results showed that the high capacitance (598 F g⁻¹ at 1.0 A g⁻¹) and more excellent capacity retention were achieved for HbG/PANI as supercapacitor electrode than that of PANI (217 F g⁻¹ at 1.0 A g⁻¹). In addition, the HbG/PANI also was exhibited fast (72 s) and reversible with the change of color at different potential (0–1 V) as electrochromic device. Excellent electrochemical properties were attributed mainly to the stable chemical bonding of HbG between PANI and ITO, which was conducive to the ion transport and electron conduction. Significantly, we proposed a smart supercapacitor and simultaneously monitored the level stored energy by visual change. The findings showed that the proposed supercapacitor with electrochromic function opens a new path for the future development of smart devices with visualized energy levels.