One-Step Synthesis Of Ordered Mesoporous Carbon And Its Application In Supports Of Catalysts

Ordered mesoporous carbon with 2D hexagonal structure derived from the co-assembly of F127 and resol had been successfully synthesized in one-step. The BET surface area, total pore volume, and pore diameter of the mesoporous carbon was 615.6 m2·g-1, 0.35 cm3·g-1, and 2.7 nm, respectively. Pt nanoparticles supported on the mesoporous carbon were fabricated by a facile CTAB assisted microwave synthesis process, wherein CTAB was expected to improve the wettability of carbon support as well as the dispersion of Pt nanoparticles. Thereby, the electrocatalytic activity of Pt nanoparticles for adsorbed hydrogen was enhanced. The electrochemical active surface area of Pt nanoparticles prepared with CTAB (70.2 m2/g) was two times than that without CTAB.Carbon nanofiber was synthesized through a hard template of AAO (anodic aluminum oxide) membrane together with a soft template of block copolymer surfactant F127. It exhibited hierarchical mesoporous structure combining regular spiral channels with round pores. Pt nanoparticles supported on the carbon nanofiber displayed superior performances in sulfuric acid. Its electrochemical active surface area for hydrogen oxidation was 181.1 m2/g, which was 5.5 times than that of Pt nanoparticles supported on mesoporous carbon powders.In order to reduce structural shrinkage during the carbonization, mesoporous carbon frameworks were reinforced by introducing silica into the nanocomposites. The mesoporous carbon, wherein the percentage of the carbon-compound content in the carbon-silica nanocomposite was 40%, possessed high BET surface area of 1330 m2/g, large pore diameter of 6.4 nm, and pore volume of 2.13 cm3/g. Pt nanoparticles supported on this carbon gave the excellent electrocatalytic activity for adsorbed hydrogen. Its electrochemical active surface area for hydrogen oxidation was 220.8 m2/g, which was 7 times than that of Pt nanoparticles supported on carbon material without silica.Mesoporous carbon supports further modified by the rare earth oxides were expected to improve the utilization of noble metal while develop the synergetic catalysis. After modified by Pr2O3, mesoporous carbon loading with PtRu nanoparticles had the lowest charge transfer resistance and the highest Warburg coefficient of diffusion in the electrochemical reactions. In system of sulfuric acid, its electrochemical active surface area for hydrogen oxidation was 136.3 m2/g, which was 3.5 times than that of PtRu/C. In system of methanol, it showed high peak current density of 21.8 mA/cm2 for methanol oxidation, while presented the slower decay of current than PtRu/C, indicating the improved CO-tolerance.