Phosphomolybdic acid-doped polypyrrole as electrode for integrated hydrogel supercapacitors
摘要
Integrated hydrogel supercapacitors have attracted increasing attention owing to their low interfacial contact resistance and excellent electrochemical performance even under folding and bending. Herein, phosphomolybdic acid-doped polypyrrole (PPy) was deposited in situ on the surface of a hydroxypropyl cellulose/polyvinyl alcohol (HPC/PVA) hydrogel to fabricate integrated hydrogel supercapacitors. The negatively charged phosphomolybdic acid (PMo12) was anchored onto the positively charged PPy chain to prevent its dissolution in the electrolyte thereby enhancing its pseudocapacitive performance. PMo12 also can dope and modify PPy, providing additional pseudocapacitance and thereby improving the energy storage capacity of the supercapacitor. The supercapacitor achieved a high areal specific capacitance (350 mF cm−2 at 0.5 mA cm−2) and demonstrated a remarkable energy density (24.0