Amphiphilic carbonaceous material-based hierarchical porous carbon aerogels for supercapacitors

Abstract

Novel hierarchical porous carbon aerogels (PCAs) derived from amphiphilic carbonaceous material (ACM) have been mass-prepared via a facile solvent exchange induced self-assembly process and subsequent carbonization and KOH activation. The resulting products are stacked up by highly interconnected carbon nanoparticles with a certain amount of micropores and mesopores, which aggregate to build a three-dimensional macroporous architecture. The hierarchical porous structure facilitates fast ion transportation inside the electrode simultaneously preserving efficient ion surface electrochemical reactions. Capacitive and rate performances were evaluated by fabricating symmetric capacitors with both aqueous and organic electrolytes. The PCA-0.5 and PCA-1.0 electrodes exhibit superior specific capacitances of 261.2 and 227.9 F g⁻¹ at a current density of 0.05 A g⁻¹ in 6 M KOH electrolyte, and still remain 145.5 and 175.4 F g⁻¹ as the current density increases to 100 A g⁻¹, respectively. Remarkably, the PCA-0.5 and PCA-1.0 electrodes show stable cycle durability with a slight capacitance loss of 8.2 and 11.2 % after 5000 cycles at 1 A g⁻¹, respectively. Furthermore, in organic electrolyte system, the PCA-1.0 electrode manifests an outstanding capacitance of 155.4 F g⁻¹ at a current density of 0.05 A g⁻¹. The encouraging results demonstrate that PCAs are a sort of promising and competitive supercapacitors electrode materials.