Balancing Porosity and Oxygen‐Containing Functionalities of Hierarchically Porous Carbons for Enhanced Capacitive Supercapacitors

Abstract

Herein, a strategy by balancing porosity and oxygen‐containing functionalities is successfully developed to efficiently modulate pore structures as well as relevant capacitive performance toward hierarchically porous carbon materials. It is revealed that the mass ratio of sodium citrate (producing porosity by a self‐template) and F‐127 (producing both porosity and pseudocapacitance) exerts a crucial role for achieving the aforementioned objective. In addition, when the mass ratio of sodium citrate to F‐127 reaches up to 1:1, the carbon sample delivers an excellent cycling stability of 98% within 10 000 cycles and the superior energy densities of 3.6 and 10.6 W h kg−1 when using 6 m KOH and 1 m Na2SO4 (voltage up to 1.8 V) as electrolytes, respectively, in a two‐electrode configuration. Thereby, by balancing the porosity (contribution to transport of electrolytes) and oxygen functionalities (contribution to additional pseudocapacitance), the present carbon materials enable integrated capacitive improvement for supercapacitors. The present scientific strategy of balancing porosity and heteroatom‐doping functionalities can be readily extended for producing other kinds of porous carbon materials especially used in the area of supercapacitors.