Synthesis of spherical mesoporous carbon for electric double-layer capacitors

Resorcinol and formaldehyde were used as carbon precursors, poly(ethylene oxide)-poly(propylene oxide)-poly(ethylene oxide) triblock copolymer was employed as a soft template, and tetraethylorthosilicate-generated silica was used as hard templates to synthesize spherical mesoporous carbon. The resulting spherical mesoporous carbons were characterized by nitrogen adsorption–desorption isotherms and electron microscopy (SEM and TEM) and used as electrode materials for aqueous electric double-layer capacitors. The average diameters of spherical particles ranged from 2 to 7 μm and the mesopore was ca 2 nm. The highest specific surface area of 1,000 m²/g and mesopore volume of 0.86 cm³/g was obtained. The specific capacitance of 130 F/g was obtained by means of galvanostatic charging/discharging and cycle voltammetry.