Carbonyl-enriched hierarchical carbon synergizes redox electrolyte for highly-efficient and stable supercapacitors

Abstract

Carbonyl-functionalized carbon porous leaves modifying carbon channels have been reported via single-step wood carbonization. A redox reaction between carbonyl and cupric chloride endows the freestanding electrode with an ultrahigh area specific capacitance of 13.1 F cm⁻² (30 mA cm⁻²) and over 99.6% retention after 45 000 cycles in supercapacitors.