3-Aminophenol: A novel redox additive in acidic environment enhancing pseudocapacitance for binary intercrossing hydrogel based supercapacitor

To enhance the electrochemical performance of flexible solid-state supercapacitors, the effective utilization of pseudocapacitance, induced by redox components, is imperative. In this study, we developed a polyacrylamide (PAM)/PEG binary intercrossing hydrogel skeleton, using the acrylamide in situ polymerization method. We incorporated 3-aminophenol (3-AP) and acid into the system to leverage its redox surface capacitance and improve its electrolyte morphology, thereby increasing the specific capacitance of the device. Additionally, it is observed that the interconnected macromolecular scaffold can effectively decrease the diffusion distance of electrolyte ions, leading to an optimal pH value and 3-AP concentration achieved via the oxidation-reduction process. At a scanning current of 0.1 A g⁻¹, the specific capacitance reaches an impressive 120.6 F g⁻¹. Furthermore, a notable increase in both energy density and power density is achieved, reaching 6.6 W h kg⁻¹ and 625 W kg⁻¹, respectively. This groundbreaking approach to enhancing capacitance in quasi-solid hydrogel supercapacitors offers a promising avenue for further exploration.