Fabrication of conductive carbonaceous spherical architecture from pitch by spray drying

Abstract

Continuous spray drying used to synthesize amphiphilic sulfonated pitch-based spherical nanoparticles was reported in this study. The spherical particles were further carbonized and activated by KOH to obtain porous spheres. N2 adsorption–desorption, mercury porosimetry and Raman spectroscopy were used to investigate the pore structure and electron conductivity of the resulting spherical activated carbon particles. The results show that the porous spheres had a high specific surface area (e.g., up to 2550m2g−1) and a continuous pore size distribution that varied from micropores to macropores. This interconnected 3-D carbonaceous architecture efficiently improved the electrical conductivity and facilitated a better utilization of the inner-pores for energy storage. These two aspects combine together to guarantee a low internal resistance and a good rate performance to an EDLC using these spherical nanoporous carbons as the electrodes. In 1M TEA-BF4/PC solution, such EDLC showed a specific capacitance of 173Fg−1 at 0.05Ag−1 and 115Fg−1 at 10Ag−1. Its energy density gets to 43.8Whkg−1 and maintains at 24.16Whkg−1 even the power density rises up to 25kWkg−1.