Influence of nitric acid oxidation on the supercapacitive performance of mesoporous carbons with different pore symmetries

摘要

Two kinds of mesoporous carbons (MPC) with three-dimensional (3D) body-centered cubic (Im3m) and 2D hexagonal symmetry (p6m) were synthesized by using triblock copolymer PEO-PPO-PEO (F127) and diblock copolymer polydimethylsiloxane-poly(ethylene oxide) (PDMS-PEO) as co-templates and were further activated by nitric acid oxidation. The electrochemical performances of MPCs and acid-modified MPCs (H-MPCs) electrodes were investigated. After nitric acid modification, the capacitive performances of MPCs were obviously improved. The acid-modified sample with 2D p6m symmetry (H-2D-MPC) exhibited the highest specific capacitance of 237.1 F g~(-1) in 6 M KOH at the current density of 1 A g(-1) and could be a potential candidate for supercapacitors.