Uniform fibrous-structured hollow mesoporous carbon spheres for high-performance supercapacitor electrodes

Uniform fibrous-structured hollow mesoporous carbon spheres (FHMCSs) have been synthesized by a simple template method using fibrous-structured mesoporous silica microspheres and resol precursor as silica template and carbon sources, respectively. It is found that FHMCSs have an ultra high specific surface area of 1121 m2 g−1 and large pore volume of 1.3 cm3 g−1. The high surface-to-volume ratio is a favorable factor to obtain high specific capacitance and excellent rate performance. As expected, when used as supercapacitor electrodes, the FHMCSs exhibit high specific capacitance of 359.2 F g−1 at current density of 1 A g−1 and excellent cycle stability (92% retention after 5000 cycles). The energy density of the FHMCSs can be estimated to be 49.9 Wh kg−1 at a power density of 500 Wh kg−1. Moreover, the FHMCSs electrode shows high energy density of 36.4 Wh kg−1 even at the power density of 10000 W kg−1, suggesting a potential application in supercapacitors and other energy storage fields.