Green synthesis of hierarchical porous carbon with adjustable porosity for high performance supercapacitors

Abstract We prepared hierarchical porous carbon based on the metathesis reaction of K2CO3 with CH3COOH. During carbonization, the reactant (K2CO3) and the reaction product (CH3COOK) acted as activators and templates. The influence of the ratio of K2CO3/CH3COOK on the electrochemical performance of hierarchical porous carbon was explored. The obtained porous carbon has a high specific surface area (2289 m2 g−1) and adjustable micro-/mesoporous porosity. When the molar ratio of K2CO3/CH3COOK is 1, the specific capacitance is 374.4 F g−1 at 1 A g−1, and the capacitance retention rate reaches 76.4% when the current density increases to 10 A g−1. The assembled symmetrical supercapacitor (PC-2/PC-2) has a excellent cycle stability in 1 M Na2SO4 within the voltage window of 0–2.0 V. When the power density is 500.02 W kg−1, the maximum energy density of 29.14 Wh kg−1 is obtained. These results show superb performance in supercapacitor based on the metathesis reaction of K2CO3 with CH3COOH.