Electrodeposited Poly(5-Amino-2-Naphthalenesulfonic Acid-co-o-Aminophenol) as the Electrode Material for Flexible Supercapacitor

Copolymers of 5-amino-2-naphthalenesulfonic acid (ANS) and o-aminophenol (oAP) are electropolymerized on carbon cloth substrate from aqueous solutions, and the electropolymerization process is investigated using electrochemical quartz-crystal microbalance. The surface of the copolymer (PANS-co-oAP) appears rough and is capable to store charge as the battery-type electrode in 1 m H2SO4 (102.9 mAh g(-1) at 1 A g(-1)) or in 1 m ZnSO4 (79.75 mAh g(-1) at 1 A g(-1)) aqueous solutions. Compared with PANS and PoAP, the high specific capacity of the PANS-co-oAP is originated from the increased number of electrochemically active sites and increased diffusion rates of ions. Evidence of amino/imino and hydroxyl/carbonyl groups redox processes and cation insertion and extraction are given by ex situ X-ray photoelectron spectroscopy. When used as the electrode material in the flexible solid-state supercapacitors, the specific capacitance is at 37.9 F g(-1) which does not significantly alter with the bending angle. The flexible solid-state supercapacitor shows a specific energy of 5.4 Wh kg(-1) and a power density of 250.3 W kg(-1) at 0.5 A g(-1), and a high capacitance retention (88.2%) after 3000 cycles at 5 A g(-1) is achieved.

Automated summary

Copolymers of 5-amino-2-naphthalenesulfonic acid (ANS) and o-aminophenol (oAP) were electropolymerized on a carbon cloth substrate from aqueous solutions. The resulting copolymer exhibited a rough surface and could store charge, resulting in high specific capacity. X-ray photoelectron spectroscopy confirmed the mechanism of charge storage. When used as electrode material in flexible solid-state supercapacitors, the copolymer showed high specific energy and power density, with a high capacitance retention even after many cycles.