2022/06/13

Estimation of the spatial distribution of carbon edge sites in a carbon structure using H2 desorption kinetics in temperature programmed desorption https://doi.org/10.1016/j.carbon.2022.06.006 This study aims to elucidate the role of hydrogen desorption profiles obtained through temperature programmed desorption (TPD) analysis of carbon materials for revealing their carbon edge sites. Accordingly, the H2 desorption profiles of several carbon materials, such as activated carbon, carbon black, reduced graphene oxide (rGO), phenol resin carbon, graphite, high-temperature treated carbon, and carbo...続きを読む »

2022/05/03

Modulation of the electronic state of carbon thin films by inorganic substrates https://www.sciencedirect.com/science/article/pii/S0008622322003578?via%3Dihub The control of the electronic states of carbon-based materials is of great importance for the widespread use of carbon materials as electronic devices and catalysts. This article reports a novel method of controlling the electronic states of carbon-based materials by establishing covalent bonds between inorganic support materials and carbon thin films. Carbon thin films of 1 nm thickness were grown on inorganic substrates (Al2O3, Al...続きを読む »

2022/01/07

Preparation of Chemically Structure-Controlled BN-Doped Carbons for the Molecular Understanding of Their Surface Active Sites for Oxygen Reduction Reaction https://pubs.acs.org/doi/abs/10.1021/acscatal.1c04806 BN-doped carbons have been reported to exhibit higher oxygen reduction reaction (ORR) activities than single-atom-doped carbons. However, the structures of these BN-doped carbons as well as the mechanism underlying their catalytically active sites had not been elucidated. In the BN-doped carbons reported so far, B and N exist in a disordered manner within the carbon structure. Therefore,...続きを読む »

2021/08/20

Benzene hydrogenation activities of Ni catalyst supported on N- and B-doped carbons https://www.sciencedirect.com/science/article/pii/S0925963521003137?via%3Dihub A catalyst support can improve the catalytic activity of metal catalysts, and this phenomenon is well known as the support effect. The effective use of this support effect is considered important for improving catalytic activity. However, the factors affecting this phenomenon are complex. It is, therefore, important to understand the interaction between the support and metal catalyst as well as the surface characteristics of the supp...続きを読む »

2021/05/24

Direct conversion of lignin to high-quality graphene-based materials via catalytic carbonization https://pubs.rsc.org/en/content/articlelanding/2021/RA/D1RA02491D#!divAbstract Methods for effectively utilizing lignin are necessary for the realization of a sustainable society. Herein, we report a method for directly converting lignin to graphene-based materials. Fe-supported lignin is prepared by dissolving lignin in an aqueous FeCl2 solution, followed by freeze drying. Graphene is then produced by catalytically carbonizing this Fe-supported lignin at 1200 °C. The characteristics of both the Fe...続きを読む »

2020/11/28

Quantitative analysis of the formation mechanism of tightly bound rubber by using carbon-coated alumina nanoparticles as a model filler https://www.sciencedirect.com/science/article/pii/S0008622320311532?via%3Dihub Using carbon-coated alumina nanoparticles as a model filler for styrene-butadiene rubber (SBR), rubber composites with different carbon surface chemistry were prepared and the bound rubber thus formed in each composite was analyzed in relation to the carbon surface chemistry. The present approach provides quantitative understanding of the rubber-carbon interface at the molecular lev...続きを読む »

2019/11/15

カーボン表面の組成・構造と酸素還元活性 https://www.jstage.jst.go.jp/article/tanso/2019/290/2019_029007/_article/-char/ja/ This article reviews the influence of heteroatom doping and the formation of warped graphitic layers on the catalytic activity of carbons for the oxygen reduction reaction (ORR). The development of a non-platinum cathode catalyst is key for the practical use of polymer electrolyte fuel cells (PEFCs), and carbon-based ORR catalysts are receiving special attention. First, we consider studies on the enhanced ORR activity of carbons caused by heteroatom doping. The type of dopant has been extende...続きを読む »

2019/08/15

Influence of Low-temperature Oxidation on Structure of Coke Making Coal https://www.jstage.jst.go.jp/article/isijinternational/59/8/59_ISIJINT-2018-808/_article Self-exothermic reaction of coal is initiated by the reaction of coal in a pile with oxygen in the air to be oxidized. Then, the heat generated by the oxidation promotes further oxidation, resulting in ignition. In order to prevent this phenomenon, it is necessary to understand the initial stage of oxidation of coal in the condition of heat-accumulation. Conventionally, there are very few researches to understand the early stage of coa...続きを読む »

2018/03/29

Critical advancements in achieving high power and stable nonprecious metal catalyst–based MEAs for real-world proton exchange membrane fuel cell applications Dustin Banham, Takeaki Kishimoto, Yingjie Zhou, Tetsutaro Sato, Kyoung Bai, Jun-ichi Ozaki, Yasuo Imashiro, Siyu Ye Article Despite great progress in the development of nonprecious metal catalysts (NPMCs) over the past several decades, the performance and stability of these promising catalysts have not yet achieved commercial readiness for proton exchange membrane fuel cells (PEMFCs). Through rational design of the cathode catalyst layer ...続きを読む »

2017/10/02

Analyses of trace amounts of edge sites in natural graphite, synthetic graphite and high-temperature treated coke for the understanding of their carbon molecular structures Ishii, T., Kaburagi, Y., Yoshida, A., Hishiyama, Y., Oka, H., Setoyama, N., Ozaki, J., Kyotani, T. Article Trace amounts of edge sites in natural graphite, synthetic graphite and high-temperature treated coke are quantitatively analyzed from the numbers of hydrogen atoms and oxygen-containing functional groups at carbon edge sites. For the analysis of hydrogen content, a new analytical technique is developed. The oxygen-con...続きを読む »