Preparation, structural characterization, and electrochemical properties of chemically modified mesoporous carbon

A series of chemically modified ordered mesoporous carbon materials (FC-x, x = 0, 0.5, 1.0, 1.5, 2.0, and 3.0) were prepared by an easy oxidation method in nitric acid aqueous solution. Fourier transform infrared spectroscopy study indicated that the content of the functional groups, such as –COOH and C–OH, increased as a function of oxidation treatment time. Both small-angle X-ray diffraction patterns and transmission electron micrographs confirmed that the ordered mesostructures were preserved after surface oxidation. Nitrogen adsorption measurement showed that the specific surface area and pore size of the carbon materials first increased and then decreased when the oxidation time was longer. The chemically modified ordered mesoporous carbon materials showed better capacitance performance than that of the CMK-3 without acid treatment. The introduced functional groups produced pseudo-capacitance, which resulted in an increase in specific capacitance. The carbon materials treated for 1.5 h showed the highest high-rate capacity. The specific capacitance reached ∼250 F g−1 at a scan rate of 1 mV s−1.