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Highlights: [•] Mesoporous Co3O4 was prepared through template-replicating method using KIT-6. [•] Mesoporous Co3O4 showed an enhanced Fischer–Tropsch reaction activity. [•] Initial catalyst deactivation was mainly attributed to the structure collapse. [•] Deactivation was related with carbon encapsulation of aggregated cobalt particles. [Copyright &y& Elsevier]

Abstract: Carbon-supported Pt nanoparticle catalysts with ultra-high loading up to 85% are prepared by multi-step reduction (Pt/C-nR), in which additional Pt precursors are reduced upon a preformed Pt/C catalyst (Pt/C-1R). Transmission electron microscopy images show that the Pt/C-nR catalysts are composed of multilayers of Pt nanoparticles. The multiply stacked morphology in the Pt/C-nR catalysts may originate from the local overgrowth of additionally reduced Pt nanoparticles on the pre-existing Pt nanoparticles in the Pt/C-1R catalyst rather than conformal growth. The electrochemical characterizations by cyclic voltammograms in HClO4 solution reveal that Pt/C-2R catalyst exhibits an increased Pt utilization over the Pt/C-1R catalyst of the same Pt loading on the carbon support where a significant portion of catalytically active surfaces are buried within micropores of carbons. Furthermore, a direct methanol fuel cell (DMFC) single cell employing Pt/C-2R catalyst exhibits an enhanced DMFC performance compared to a single cell using the Pt/C-1R catalyst, demonstrating the importance of morphological control of Pt nanoparticles that can improve the catalyst utilization. [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]

Abstract: A series of ordered mesoporous carbon (OMC) supported Pt (Pt/OMC) catalysts with a controlled Pt size from 2.7 to 6.7nm at high Pt loading around 60wt.% have been prepared and their electrocatalytic activities for the electrode reactions relevant to the direct methanol fuel cells have been investigated. The Pt/OMC catalysts with a high dispersion (Pt size around 3nm) could be prepared by the use of a modified, sequential impregnation–reduction method. The Pt/OMC catalysts containing larger Pt particles were obtained by increasing reduction temperature under hydrogen flow and Pt loading, and by performing impregnation–reduction in a single cycle. The oxygen reduction reaction (ORR) and methanol oxidation reaction (MOR) activities of Pt/OMC catalysts as a function of Pt size were investigated at room temperature in 0.1M HClO4 and (0.1M HClO4 +0.5M methanol), respectively. The specific activity of Pt/OMC for ORR steeply increased up to 3.3nm and became independent of Pt size from 3.3 to 6.7nm, and the mass activity curve exhibited maximum activity at 3.3nm. The MOR activity of Pt/OMC also exhibited the similar trend with the ORR activity, as the maximum of mass activity was also found at 3.3nm. The results of the present work indicate that the Pt catalysts of ca. 3nm is an optimum particle size for both ORR and MOR, and this information may be translated into design of high performance membrane electrode assembly. [Copyright &y& Elsevier]

Abstract: Highly efficient catalytic carbon–carbon bond-forming reactions between aryl chlorides and Grignard reagents have been achieved using nickel (II) ion on nanoporous carbon. The catalytic activities in these reactions were so high that the effects of preparation, reduction, and phosphines could not be observed. No positional effect in the substrates was monitored. Increased formation of homocoupling products with functionalized substrates was also observed and a plausible explanation based on the competitive adsorption between substrates and Grignard reagents was proposed. [Copyright &y& Elsevier]

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: Much improved catalytic carbon–carbon bond-forming reactions between aryl chlorides and Grignard reagents has been achieved using nickel(II) ion on nanoporous carbon. [Copyright &y& Elsevier]

Various kinds of mesoporous metal oxides with high thermal stabilities as well as crystalline frameworks have been successfully prepared using a mesoporous carbon as a template via nano-replication technique. This noble synthesis strategy for the preparation of mesoporous materials was carried out by the impregnation with the desired metal precursor. The mesoporous metal oxides calcined at 823 K exhibited 100–400 m2/g of BET surface areas and 3–12 nm of pore sizes. The frameworks of the mesoporous metal oxide materials were crystallized by heat treatment at 1073 K in N2 flow before the template removal. The results indicate that the mesoporous metal oxides can be obtained by the faithful negative replication of the structure of the mesoporous carbon. [Copyright &y& Elsevier]