In situ hydrothermal deposition as an efficient catalyst supporting method towards low-temperature graphitization of amorphous carbon

Abstract

In view of the fact that the catalytic activity of supported catalyst is greatly influenced by its impregnation method, an in situ hydrothermal deposition method was explored and applied to load iron catalyst onto the amorphous carbon matrix, which derived from a soft-templating method with sucrose as precursor, to prepare nanoporous graphitic carbon at low temperature. Compared to traditional impregnation method, this hydrothermal loading method could realize the phase transformation from amorphous carbon to graphitic carbon at a temperature as low as 650°C. Systematical studies on the hydrothermal deposition and catalytic graphitization were made by X-ray diffraction and Raman spectrum, indicating that hydrothermal impregnation temperature and duration are the two crucial factors to the catalytic performance of loaded iron oxide. The obtained graphitic carbon by this approach possesses a nanoporous structure with surface area up to 329m2/g, pore volume of 0.39cm3/g and achieves a capacitance per unit surface area of 39.5μF/cm2, much higher than that of the carbon derived from traditional impregnation method (24.6μF/cm2).