A novel mesoporous carbon with straight tunnel-like pore structure for high rate electrochemical capacitors

Mesoporous carbons are prepared from a mixture of the soluble starch with needle-like nano-sized Mg(OH)2 particles. The samples structures are characterized by TEM, nitrogen adsorption at 77 K and XRD. The electrochemical performance for electrochemical capacitors is evaluated in a 6 M KOH aqueous solution. The resultant carbons show a disordered pore structure with interweaving straight nano-tunnels that resembled the shape of the template, and possess a high surface area more than 1000 m2 g−1 and a large pore volume. The special one dimensional morphology of templates cause a graphitization effect on the carbon in partial region, different from catalytic graphitization mechanism of transition metal particles. Due to those characteristics, the samples exhibit good electrochemical performances used for electrochemical capacitors electrode, especially excellent power capability. The sample carbonized at 950 °C for 6 h retain a capacitance of 126 F g−1 even at a high current density of 40 A g−1.

► A novel mesoporous carbon with straight tunnel-like pore structure was prepared. ► It was observed that the special one dimensional morphology of templates caused graphitization effect on the carbon in partial region. ► The possible mechanism of the graphitization effect on the carbon of one dimensional nano-sized particle template was supposed. ► The samples exhibited good electrochemical performances for electrochemical capacitors, especially excellent power capability.