Ultrafast high-energy micro-supercapacitors based on open-shell polymer-graphene composites

Micro-supercapacitors are poised to serve as on-chip power sources for electronics. However, the challenge simultaneously increase their power, energy, and lifetime demands new material combinations beyond current carbon-based systems. Here, we demonstrate that electro-deposition of an open-shell conjugated polymer with reduced graphene oxide achieves electrodes capacitance up 186 mF cm?2 (372 F cm?3). The extended delocalization within stabilizes redox states facilitates a 3 V wide potential window, while hierarchical electrode structure promotes ultrafast kinetics. micro-supercapacitor shows high density 227 mW energy 10.5 ?Wh stability 84% retention after 11,000 cycles. These attributes allow operation at 120 Hz fast charging alternating (AC) line filtering applications, which may be suitable replace bulky electrolytic capacitors or high-endurance storage wireless