研究者詳細 - 薩摩　篤

論文 - 薩摩　篤

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Glucose Isomerization Using Alkali Metal and Alkaline Earth Metal Titanates

Ohyama J., Zhang Y., Ito J., Satsuma A.

ChemCatChem 9 巻 ( 14 ) 頁： 2864 - 2868 2017年7月

記述言語：日本語掲載種別：研究論文（学術雑誌）出版者・発行元：ChemCatChem

Glucose isomerization was performed using various titanate catalysts, which include SrTiO3, BaTiO3, CaTiO3, Na2Ti6O13, K2Ti6O13, and Sr3Ti2O7, prepared using a conventional solid-phase method. Among the titanates, SrTiO3, CaTiO3, and Na2Ti6O13 offered a relatively high fructose yield (32 %) with a high selectivity (68–78 %). The yields are comparable to yields reported previously using a Sn-modified BEA zeolite, which shows a high efficiency for glucose isomerization as a Lewis acid catalyst. A study of the mechanism of glucose isomerization on a SrTiO3 catalyst surface by using 1H NMR spectroscopy suggested that the titanates catalyze the isomerization as base catalysts. Thus, the effect of the basicity of the titanates on glucose isomerization was investigated in terms of the base quantity and strength. The analysis was performed by using an acid–base titration method and FTIR spectroscopy with CHCl3 as a probe molecule. It is proposed that glucose isomerization on the titanates depends not only on the base amount but also on the base strength.

DOI： 10.1002/cctc.201700068

Web of Science

Scopus

Hydrogenative ring-rearrangement of biomass derived 5-(hydroxymethyl) furfural to 3-(hydroxymethyl) cyclopentanol using combination catalyst systems of Pt/SiO2 and lanthanoid oxides 査読有り

J. Ohyama, Y. Ohira, A. Satsuma

CATALYSIS SCIENCE & TECHNOLOGY 7 巻 ( 14 ) 頁： 2947 - 2953 2017年7月

記述言語：英語掲載種別：研究論文（学術雑誌）出版者・発行元：ROYAL SOC CHEMISTRY

Combination catalyst systems composed of Pt/SiO2 and lanthanoid oxides (Pt/SiO2 + LOx) efficiently catalyze the hydrogenative ring-rearrangement of 5-(hydroxymethyl) furfural (HMF) in water to produce 3-(hydroxymethyl) cyclopentanol (HCPO), which can be a unique building block for new materials derived from biomass. We investigated the reason for the efficient hydrogenative ring-rearrangement on Pt/SiO2 + LOx in terms of the acid-base properties of reaction systems, since H+ and Lewis acids can affect the rearrangement of the furan ring. It is indicated that the ring-rearrangement efficiently proceeds under slightly acidic conditions (pH = 5-7) with moderate or a little weak Lewis acidity of lanthanoid oxides.

DOI： 10.1039/c7cy00712d

Web of Science

A theoretical insight into enhanced catalytic activity of Au by multiple twin nanoparticles 査読有り

Sawabe K., Koketsu T., Ohyama J., Satsuma A.

Catalysts 7 巻 ( 6 ) 頁： 191 2017年6月

記述言語：英語掲載種別：研究論文（学術雑誌）出版者・発行元：Catalysts

Recently, it has been reported that the morphology of Au nanoparticles (NPs) affects the catalytic activity of CO oxidation; twin crystal NPs show higher activity for CO oxidation than single-crystal NPs. In this study, density functional calculations have been carried out to investigate the morphology effect of Au NPs using CO as a probe molecule. In the case of Au NPs with a size of more than 2 nm, CO adsorption energy on the Au NPs is mainly determined by a coordination number (CN) of adsorption sites. CO binding to a multiple twin NP with a size of about 1 nm is stronger than that on a single-crystal NP with the same size. A simple CN explanation cannot be applied to the enhancement of CO binding to the small multiple twin NP. This enhancement is related to a deformation of the NP structure before and after CO adsorption. It is suggested that the multiple twin NP with a size of less than 1 nm, which shows the deformation upon CO adsorption, contributes to the higher activity for CO oxidation.

DOI： 10.3390/catal7060191

Web of Science

Scopus

Methane combustion over Pd/CoAl<inf>2</inf>O<inf>4</inf>/Al<inf>2</inf>O<inf>3</inf> catalysts prepared by galvanic deposition

Mahara Y., Tojo T., Murata K., Ohyama J., Satsuma A.

RSC Advances 7 巻 ( 55 ) 頁： 34530 - 34537 2017年

記述言語：日本語掲載種別：研究論文（学術雑誌）出版者・発行元：RSC Advances

Pd/CoAl2O4/Al2O3 methane combustion catalysts were synthesized using a galvanic deposition (GD) method (PdCoAl-GD). This PdCoAl-GD catalyst showed higher activities and turnover frequencies (TOFs) than conventional Pd/Al2O3. According to X-ray diffraction (XRD), X-ray absorption fine structure (XAFS) and scanning transmission electron microscopy (STEM) measurements, PdCoAl-GD was composed of a CoAl2O4 phase supported on γ-Al2O3 and dispersed Pd nanoparticles of 2-7 nm in size on CoAl2O4. Operando Pd K-edge XAFS measurements indicated that the Pd in PdCoAl-GD was oxidized to highly active methane combustion PdO species at low temperatures. PdCoAl-GD also showed high activity (light-off tests) when PdO was initially present on the catalysts. Methane temperature-programmed reaction (CH4-TPR) measurements on PdCoAl-GD revealed that PdO was reduced by CH4 at low temperatures. The GD method used herein achieved PdO species that were effective for C-H activation.

DOI： 10.1039/c7ra06150a

Web of Science

Scopus

In situ XAFS study of dynamic behavior of cu species in MFI-Zeolite under element gases of ammonia selective catalytic reduction

Ueda K., Ohyama J., Satsuma A.

Chemistry Letters 46 巻 ( 9 ) 頁： 1390 - 1392 2017年

記述言語：日本語掲載種別：研究論文（学術雑誌）出版者・発行元：Chemistry Letters

We studied the dynamic redox behavior of Cu species in zeolite matrix under NH3-SCR using in situ XAFS. Cu2+ species were slowly reduced to Cu+ in flowing NH3, and subsequent addition of NO promoted the reduction to Cu+. In the oxidation step, oxygen alone did not fully oxidize Cu+ to Cu2+, but the Cu+ species were completely oxidized to Cu2+ by NOO2. The oxidation step was slower than the reduction step, which suggested that the oxidation step (Cu+ ¼ Cu2+) is the slow step of the NH3-SCR reaction.

DOI： 10.1246/cl.170451

Scopus

Hydrogenative ring-rearrangement of biomass derived 5-(hydroxymethyl)furfural to 3-(hydroxymethyl)cyclopentanol using combination catalyst systems of Pt/SiO<inf>2</inf> and lanthanoid oxides

Ohyama J., Ohira Y., Satsuma A.

Catalysis Science and Technology 7 巻 ( 14 ) 頁： 2947 - 2953 2017年

記述言語：日本語掲載種別：研究論文（学術雑誌）出版者・発行元：Catalysis Science and Technology

Combination catalyst systems composed of Pt/SiO2 and lanthanoid oxides (Pt/SiO2 + LOx) efficiently catalyze the hydrogenative ring-rearrangement of 5-(hydroxymethyl)furfural (HMF) in water to produce 3-(hydroxymethyl)cyclopentanol (HCPO), which can be a unique building block for new materials derived from biomass. We investigated the reason for the efficient hydrogenative ring-rearrangement on Pt/SiO2 + LOx in terms of the acid-base properties of reaction systems, since H+ and Lewis acids can affect the rearrangement of the furan ring. It is indicated that the ring-rearrangement efficiently proceeds under slightly acidic conditions (pH = 5-7) with moderate or a little weak Lewis acidity of lanthanoid oxides.

DOI： 10.1039/c7cy00712d

Scopus

Investigation of controlling factor for combustion of diesel soot - Effect of oxygen containing functional groups

Hoshi S., Yamashita D., Mahara Y., Ohyama J., Satsuma A.

COMODIA 2017 - 9th International Conference on Modeling and Diagnostics for Advanved Engine Systems 2017年

記述言語：英語掲載種別：研究論文（国際会議プロシーディングス）出版者・発行元：COMODIA 2017 - 9th International Conference on Modeling and Diagnostics for Advanved Engine Systems

DPF (Diesel Particulate Filter) is effective for trapping diesel soot from diesel engines. The trapped diesel soot is removed by combustion above 600°C using excess fuels, which results in reduction of fuel economy. An effective design of DPF is strongly required to improve DPF regeneration efficiency and fuel economy; however, the internal phenomenon of diesel soot combustion on DPF is still not clarified. For an effective design of DPF, in this study, we investigated the effect of diesel soot structure on combustion temperature using real diesel soot. Soot samples were characterized by means of various physicochemical techniques: XPS (X-ray photoelectron spectroscopy), EELS (Electron Energy Loss Spectroscopy), Raman spectroscopy, TEM (transmission electron microscopy), and elemental analysis. TEM images and Raman spectra of real diesel soot showed that the difference in the crystallinity of soot was small. XPS, EELS, and elemental analysis revealed that oxygen content, which is derived from surface functional groups of - COOH, -OH, and - C=O at defect sites, was strongly affected by the engine operating conditions. The ignition temperature of diesel soot was dependent on O/C ratio measured by elemental analysis. With the increase in oxygen content of diesel soot, combustion temperatures of soot became lower. It was concluded that the concentration of oxygen containing functional groups is an essential factor for the control of the ignition temperature of diesel soot.

Scopus

Improved hydrogen oxidation reaction under alkaline conditions by ruthenium -iridium alloyed nanoparticles 査読有り

J. Ohyama, D. Kumada, A. Satsuma

J. Mater. Chem. A 4 巻頁： 15980-15985 2016年9月

NiFe2O4 as an Active Component of Platinum-Group Metal Free Automotive Three-way Catalyst 査読有り

Kakuya Ueda, Cheen Aik Ang, Yoshihiro, Itoh, Junya Ohyama, Atsushi Satsuma

Catal. Sci. Technol. 頁： in preass 2016年7月

Effect of FeOx-Modification of Al2O3 on Its Supported Au Catalyst for Hydrogenation of 5-Hydroxymethylfurfural 査読有り

Junya Ohyama, Yoshinori Hayashi, Kakuya Ueda, Yuta Yamamoto, Shigoe Arai, Atsushi Satsuma

J. Phys. Chem. C 頁： accpted 2016年6月

Formation of Ru Shell on Co/Al2O3 by Galvanic Deposition Method and Its High Catalytic Performance for Three-Way Conversion 査読有り

Junya Ohyama, Hiroyuki Ishikawa, Yuji Mahara, Takumi Nishiyama, Atsushi Satsuma

Bull. Chem. Soc. Jpn 2016年5月

Enhanced activity for methane combustion over Pd/Co/Al2O3 catalyst prepared by galvanic deposition method 査読有り

Yuji Mahara, Junya Ohyama, Takumi Tojo, Kazumasa Murata, Hiroyuki Ishikawa, Atsushi Satsuma

Catal. Sci. Tech. 頁： accepted 2016年5月

Ag-M (M: Ni, Co, Cu, Fe) Bimetal Catalysts prepared by Galvanic Deposition Method for CO oxidation 査読有り

Yuji Mahara, Hiroyuki Ishikawa, Junya Ohyama, Kyoichi Sawabe, Atsushi Satsuma

Catal. Today 265 巻頁： 2-6 2016年1月

Atomic-Scale Insight into the Structural Effect of a Supported Au Catalyst Based on a Size-Distribution Analysis Using Cs-STEM and Morphological Image-Processing 査読有り

Junya Ohyama, Akihiko Esaki, Taiki Koketsu, Yuta Yamamoto, Shigeo Arai, Atsushi Satsuma

J. Catal. 335 巻頁： 24-35 2016年1月

Investigation of Size Effect of Ag Nanoparticles on Oxygen Reduction Reaction Using Ag/Co/C Catalysts Prepared by Galvanic Deposition Method 査読有り

Junya Ohyama, Yui Okata, Yuta Yamamoto, Shigeo Arai, Atsushi Satsuma

Catal. Lett. 146 巻頁： 22-27 2015年11月

Low temperature combustion over supported Pd catalysts - Strategy for catalyst design 招待有り査読有り

Atsushi Satsuma, Kaoru Osaki, Masatoshi Yanagihara, Junya Ohyama, Kenichi Shimizu

Catal. Today 258 巻頁： 83-89 2015年10月

Preparation of TiO2-Supported Twinned Gold Nanoparticles by CO Treatment and Their CO Oxidation Activity 査読有り

Junya Ohyama, Taiki Koketsu, Yuta Yamamoto, Shigeo Arai, Atsushi Satsuma

Chem. Commun. 51 巻頁： 15823-15826 2015年10月

Effect of Heterogeneous Acid-Base Catalysis on Conversion of 5-Hydroxymethylfurfural into A Cyclopentanone Derivative 査読有り

J. Ohyama, R. Kanao, Y. Ohira, A. Satsuma

Green Chemistry 頁： article online 2015年9月

Automotive Three Way Catalytic Activity of Fe-Ni/Ceria

Atsushi Satsuma, Kakuya Ueda, Yoshihiro Ito, Cheen Aik Ang, Junya Ohyama

Chem. Lett. 44 巻 ( 5 ) 頁： 703-705 2015年2月

Substrate Specific Heterogeneous Catalysis of CeO2 by Entropic Effects via Multiple Interactions 査読有り

Masazumi Tamura, Kyoichi Sawabe, Keiichi Tomishige, Atsushi Satsuma, Ken-Ichi Shimizu

ACS Catalysis 5 巻 ( 1 ) 頁： 20–26 2014年11月

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