Pore Structures of Carbon Aerogels and Their Effects on Electrochemical Supercapacitor Performance

Control of the pore structures of carbon aerogels (CAs) was investigated by changing the sol-gel polymerization and activation conditions. The morphologies and physical properties of the CAs and KOH activated carbon aerogels (ACAs) were characterized by scanning electron microscopy (SEM) and N-2 adsorption isotherms. The electrochemical performances of the CAs and ACAs as electrode materials were characterized using cyclic voltammetry (CV), a galvanostatic charge-discharge test, and electrochemical impedance spectroscopy (EIS). The results showed that the well developed three-dimensional nano-network structures and the reasonable pore size distributions of the CAs have great effect on their electrochemical performance in supercapacitors. Because of abundant mesopores and a high specific surface area (1480 m(2) . g(-1)), the specific capacitance of a ACA electrode in 6 mol . L-1 KOH electrolyte was approximately 216 F . g(-1) at a scan rate of 100 mV . s(-1). A simple model was used to investigate the role of the pores in electrochemical performance.