Protonic acid catalysis to generate fast electronic transport channels in O-functionalized carbon textile with enhanced energy storage capability

Oxygen (O) functionalized carbon materials can provide high charge storage because of their enrichment in redox-active sites, but they do not display fast charge transfer kinetics, which is caused by the loss of electrical conductivity from the disruption of sp² carbon networks. To address this challenge, we develop a novel two-step protonic acid catalysis method that partially re-establishes a π-π conjugated system for engineering fast electronic transport channels in an O-functionalized carbon textile. This method largely maintains the sp² carbon network integrity with abundant active O-functional groups embedded into a graphitic carbon host. The resultant functionalized carbon textile features both high O-content and high electrical conductivity. When incorporated in flexible electrodes for supercapacitors, the material exhibits ultrahigh areal capacitance of 2580 mF cm⁻² and excellent rate performance, outperforming other reported carbon-based flexible electrodes. The constructed flexible supercapacitor also delivers excellent electrochemical performance and mechanical stability under flexible deformations. Such a system might shed light on the design of O-functionalized carbon materials with both high O-content and high electrical conductivity for energy storage/conversion.