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Abstract: Three ordered mesoporous carbon materials (OMC) were prepared by pyrolysis of sucrose filled in the mesoporous channels of SBA-15 at three different temperatures of 600°C (OMC-600), 850°C (OMC-850) and 1100°C (OMC-1100), and followed by dissolution of the silica matrix in hydrofluoric acid. The pore structures and surface characteristics of the OMC materials were evaluated using XRD, nitrogen adsorption, FTIR spectroscopy, pH of carbon surface, and the amount of acidic surface groups from Boehm titration, respectively. The increase of the pyrolysis temperature resulted in an increase in surface pH, but a decrease in the amount of acidic surface groups. The surface area and micro- and mesopore volumes increased by increasing the pyrolysis temperature from 600°C to 850°C, but there were no significant changes in these properties above 850°C. In this paper, adsorption characteristics of methyl mercaptan on the OMC materials were studied using a dynamic adsorption method in a fixed bed. The results showed that the adsorption of methyl mercaptan was strongly influenced by pore structure and surface chemistry of the OMC. [Copyright &y& Elsevier]

Abstract: Hierarchical structure with macropores interconnecting mesopores of carbon material can remarkably improve the rate performance of electric double layer capacitor. However, pre-formed hard templates such as silica particles or polymer beads have been used in most synthetic procedures for them, resulting in an increase of manufacturing cost and time. Herein, we report novel method for synthesizing hierarchically structured macro/mesoporous partially graphitized carbon (MMPGC) for high power supercapacitor electrode material without pre-formed hard template. Instead of hard template, emulsion/block co-polymer co-template was used for generating macropores and mesopores, respectively. As a supercapacitor electrode material, MMPGC showed higher capacity retention at high current than ordered mesoporous carbon, which is characterized by cyclic voltammetry, galvanostatic charge–discharge. In addition, the effect of macropores and partially graphitized wall on reducing resistance of supercapacitor electrode was analyzed in detail with electrochemical impedance spectroscopy fitting method. [Copyright &y& Elsevier]

Abstract: Pt nanoparticles on sulfur-containing ordered mesoporous carbon (Pt/S-OMC) are obtained with 3nm in size and 60wt.% loading. XPS analysis shows that there is a strong metal-support interaction between Pt nanoparticles and S atoms embedded on the OMC support. This strong metal-support interaction fastens Pt nanoparticles upon the support and alters the electronic state of Pt from Pt0 of bulk Pt to a slightly charged state of Pt δ+. These features result in an improvement both in electrochemical stability and oxygen reduction reaction kinetics compared to Pt/OMC where the OMC does not have sulfur atoms. The approach of tuning the electronic state and the interaction of Pt on carbon supports by embedding heterogeneous atoms into the OMC can effectively improve the stability and catalytic activity of Pt nanoparticles. [Copyright &y& Elsevier]