Faculty Profiles - SATSUMA, Atsushi

Papers - SATSUMA, Atsushi

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In situ/operando spectroscopic studies on NH<inf>3</inf>–SCR reactions catalyzed by a phosphorus-modified Cu-CHA zeolite Open Access

Hiroe Kubota, Chong Liu, Takehiro Amada, Kenichi Kon, Takashi Toyao, Zen Maeno, Kakuya Ueda, Atsushi Satsuma, Nao Tsunoji, Tsuneji Sano, Kenichi Shimizu

Catalysis Today Vol. 376 page： 73 - 80 2020

Language：English Publishing type：Research paper (scientific journal)

The modification of Cu-exchanged zeolites with phosphorus represents a promising method to enhance their hydrothermal stability, which is of pivotal importance for catalysts that promote the selective catalytic reduction of NO with ammonia (NH –SCR). In this study, we investigated the reaction mechanism of NH –SCR catalyzed by a phosphorus-modified CHA zeolite that contains active Cu species (Cu-P-CHA), and assessed the effect of the phosphorus modification on the hydrothermal stability of the catalyst by employing in situ/operando spectroscopic methods. In their entirety, the combined results from in situ/operando IR, UV–vis, and XANES experiments revealed that the NH –SCR process over Cu-P-CHA proceeds via the reduction of Cu(II) to Cu(I) followed by a reoxidation of Cu(I) to Cu(II). In addition, we found that the phosphorus modification improved the hydrothermal durability of the catalyst by retaining a higher amount of the redox-active Cu species and the zeolite framework. 3 3 3

DOI： 10.1016/j.cattod.2020.07.084

Scopus

Exploiting Metal-Support Interactions to Tune the Redox Properties of Supported Pd Catalysts for Methane Combustion Reviewed

Murata, Kazumasa, Kosuge, Daichi, Ohyama, Junya, Mahara, Yuji, Yamamoto, Yuta, Arai, Shigeo, Satsuma, Atsushi

ACS Catalysis Vol. 10 ( 2 ) page： 1381 - 1387 2020

Gas-phase synthesis of morphology-controlled Pt nanoparticles and their impact on cinnamaldehyde hydrogenation

Kato Sosuke, Ohyama Junya, Machida Masato, Satsuma Atsushi

CATALYSIS SCIENCE & TECHNOLOGY Vol. 9 ( 9 ) page： 2097-2102 - 2102 2019.5

Tandem Base-Metal Oxide Catalyst: Superior NO Reduction Performance to the Rh Catalyst in NO-C3H6-CO-O-2

Ueda Kakuya, Tsuji Masashi, Ohyama Junya, Satsuma Atsushi

ACS CATALYSIS Vol. 9 ( 4 ) page： 2866-2869 - 2869 2019.4

Surface modification of Pt nanoparticles with other metals boosting the alkaline hydrogen oxidation reaction

Okubo Keiichi, Ohyama Junya, Satsuma Atsushi

CHEMICAL COMMUNICATIONS Vol. 55 ( 21 ) page： 3101-3104 - 3104 2019.3

Enhanced alkaline hydrogen oxidation reaction by modifying Pt nanoparticle surface with another metal

Ohyama J., Okubo K., Satsuma A.

ECS Transactions Vol. 92 ( 8 ) page： 733 - 738 2019

Language：Japanese Publishing type：Research paper (scientific journal) Publisher：ECS Transactions

The cell performance of anion exchange membrane fuel cells (AEMFCs) has been getting closer to that of proton exchange membrane fuel cells (PEMFCs) by improvement of hydrogen oxidation reaction (HOR) catalysts on anodes with the help of the state-of-the-art AEMs having high ion conductivity. However, development of the alkaline HOR catalysts is still demanded to reduce the usage of precious metals on AEMFC anode. Here, Pt/C catalyst is modified to improve the HOR activity using fifteen metals on the group 4-11 of the 4th and 5th period in the periodic table except for Tc, i.e., Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zr, Nb, Mo, Ru, Rh, Pd, Ag. In addition, the hydrogen binding energy of modified Pt/C and the oxophilicity of modifying metals are evaluated to reveal the mechanism of improved/lowered HOR activity.

DOI： 10.1149/09208.0733ecst

Scopus

In situ and operando analysis of environmental catalysts - Studies on reaction mechanism and active site

Murata K., Ueda K., Mahara Y., Ohyama J., Satsuma A.

Catalysis Vol. 31 page： 242 - 266 2019

Language：Japanese Publishing type：Research paper (scientific journal) Publisher：Catalysis

In situ and operando analyses are the methods to observe the real features of catalysts under the reaction conditions. These methods can clarify the dynamics of active species of catalysts and reaction scheme on catalyst surface through transient response method, kinetic study, temperature dependence of catalysts and products, and so on. In this review, progress in in situ and operando analyses is summarized with emphasis on environmental catalysts, i.e., catalysts for combustion, selective reduction of NO, automotive three-way catalysis, and related materials.

DOI： 10.1039/9781788016971-00242

Scopus

Structure-Activity Relationship of Iron Oxides for NO Reduction in the Presence of C3H6, CO, and O-2 Reviewed

Ueda, Kakuya, Ohyama, Junya, Sawabe, Kyoichi, Satsuma, Atsushi

Chemistry - A European Journal Vol. 25 ( 61 ) page： 13964 - 13971 2019

Shape Control Preparation of Supported Platinum Nano-octahedra by Ethylene Treatment for Enhancement of Selective Hydrogenation of Cinnamaldehyde Reviewed

Ohyama, Junya, Kato, Sosuke, Machida, Masato, Satsuma, Atsushi

Chemistry Letters Vol. 48 ( 10 ) page： 1203 - 1205 2019

Quantum Chemical Computation-Driven Development of Cu-Shell-Ru-Core Nanoparticle Catalyst for NO Reduction Reaction Reviewed

Ohyama, Junya, Shibano, Jumpei, Satsuma, Atsushi, Fukuda, Ryoichi, Yamamoto, Yuta, Arai, Shigeo, Shishido, Tetsuya, Asakura, Hiroyuki, Hosokawa, Saburo, Tanaka, Tsunehiro

The Journal of Physical Chemistry C Vol. 123 ( 33 ) page： 20251 - 20256 2019

Identification of active sites in CO oxidation over a Pd/Al2O3 catalyst Reviewed Open Access

Murata, Kazumasa, Eleeda, Eleen, Ohyama, Junya, Yamamoto, Yuta, Arai, Shigeo, Satsuma, Atsushi

Physical Chemistry Chemical Physics Vol. 21 ( 33 ) page： 18128 - 18137 2019

Twinned/untwinned catalytic gold nanoparticles identified by applying a convolutional neural network to their Hough transformed Z-contrast images

Yamamoto Yuta, Hattori Mizuki, Ohyama Junya, Satsuma Atsushi, Tanaka Nobuo, Muto Shunsuke

MICROSCOPY Vol. 67 ( 6 ) page： 321-330 - 330 2018.12

Synthesis of Supported Bimetal Catalysts using Galvanic Deposition Method

Mahara Y., Ohyama J., Sawabe K., Satsuma A.

Chemical Record Vol. 18 ( 9 ) page： 1306 - 1313 2018.9

Language：Japanese Publishing type：Research paper (scientific journal) Publisher：Chemical Record

Supported bimetallic catalysts have been studied because of their enhanced catalytic properties due to metal-metal interactions compared with monometallic catalysts. We focused on galvanic deposition (GD) as a bimetallization method, which achieves well-defined metal-metal interfaces by exchanging heterogeneous metals with different ionisation tendencies. We have developed Ni@Ag/SiO2 catalysts for CO oxidation, Co@Ru/Al2O3 catalysts for automotive three-way reactions and Pd−Co/Al2O3 catalysts for methane combustion by using the GD method. In all cases, the catalysts prepared by the GD method showed higher catalytic activity than the corresponding monometallic and bimetallic catalysts prepared by the conventional co-impregnation method. The GD method provides contact between noble and base metals to improve the electronic state, surface structure and reducibility of noble metals.

DOI： 10.1002/tcr.201700084

Scopus

Time Resolved in situ DXAFS Revealing Highly Active Species of PdO Nanoparticle Catalyst for CH<inf>4</inf> Oxidation

Mahara Y., Murata K., Ueda K., Ohyama J., Kato K., Satsuma A.

ChemCatChem Vol. 10 ( 16 ) page： 3384 - 3387 2018.8

Language：Japanese Publishing type：Research paper (scientific journal) Publisher：ChemCatChem

The highly active species of Pd/Al2O3 catalysts for methane combustion was revealed by in situ time-resolved dispersive X-ray absorption fine structure (DXAFS) spectroscopy. By using CH4 as a reduction agent, PdO in Pd/Al2O3 is reduced in a 2-step model involving Pd0 nucleation and growth of Pd0 domain in a PdO particle. Kinetic analysis of the 2-step model reduction of PdO nanoparticles leads to a suggestion that partial formation of Pd0 in a PdO particle accelerates methane combustion.

DOI： 10.1002/cctc.201800573

Scopus

Formation of Rhodium Metal Ensembles that Facilitate Nitric Oxide Reduction over Rhodium/Ceria in a Stoichiometric Nitric Oxide–Carbon Monoxide–Propene–Oxygen Reaction

Junya Ohyama, Takumi Nishiyama, Atsushi Satsuma

ChemCatChem Vol. 10 ( 7 ) page： 1651 - 1656 2018.4

Language：English Publishing type：Research paper (scientific journal) Publisher：Wiley Blackwell

A series of ceria-supported Rh nanoparticles (NPs) that have various particle sizes of 2–7 nm was prepared to investigate the size effect of Rh NPs on NO reduction in NO–CO–C3H6–O2 under stoichiometric conditions. The turnover frequency (TOF) for NO reduction on Rh NPs increased drastically according to their particle size. The strong size dependence of the TOF was attributed to the oxidation states of Rh NPs but not to particle geometries, which include fractions of surface local sites (e.g., corner, edge, plane) and the surface crystal structures (e.g., Rh(1 1 1), (1 0 0)). The variation of the TOF with the Rh metal fraction suggested that Rh metal ensembles are highly active species for NO reduction.

DOI： 10.1002/cctc.201701842

Scopus

Enhanced three way catalytic activity of NiFe2O4 by physically mixed metal oxides

Shiori Nagai, Kakuya Ueda, Junya Ohyama, Atsushi Satsuma

Catalysis Today Vol. 303 page： 40 - 45 2018.4

Language：English Publishing type：Research paper (scientific journal) Publisher：Elsevier B.V.

The NOx reduction activity of NiFe2O4 in automotive three-way catalysis was enhanced by physical mixing with CeO2, MgO, ZrO2, and Al2O3, while the mixing with TiO2 and Nb2O5 did not promoted the catalytic activity. On both pure NiFe2O4 and the physically mixed catalysts, NO was mainly reduced by C3H6 under the NO-C3H6-CO-O2 reaction conditions, because the temperature dependence of NO conversion in NO-C3H6-CO-O2 reaction was the same as that in NO-C3H6-O2 reaction. The in-situ FT/IR measurement revealed that the NO reduction proceeded with (1) partial oxidation of C3H6 to surface carboxylates, i.e., acetate and formate as good reductants for NO, and (2) reduction of NO by surface carboxylates. The metal oxide additives did not have catalytic activity for partial oxidation of C3H6 nor for NO oxidation to NO2, except CeO2. The main promotion effect was attributed to storage and release of surface carboxylates by metal oxide additives.

DOI： 10.1016/j.cattod.2017.07.026

Scopus

Direct Synthesis of Lactams from Keto Acids, Nitriles, and H2 by Heterogeneous Pt Catalysts

S. M.A.H. Siddiki, Abeda S. Touchy, Ashvini Bhosale, Takashi Toyao, Yuji Mahara, Junya Ohyama, Atsushi Satsuma, Ken-Ichi Shimizu

ChemCatChem Vol. 10 ( 4 ) page： 789 - 795 2018.2

Language：English Publishing type：Research paper (scientific journal) Publisher：Wiley Blackwell

We report herein the first general catalytic system for the direct synthesis of N-substituted γ- and δ-lactams by reductive amination/cyclization of keto acids (including levulinic acid) with nitriles and H2 under mild conditions (7 bar H2, 110 °C, solvent free). The most effective catalyst, Pt and MoOx co-loaded TiO2 (Pt-MoOx/TiO2), shows a wide substrate scope, high turnover number (TON), and good reusability.

DOI： 10.1002/cctc.201701355

Scopus

Dynamic Behavior of Rh Species in Rh/Al<inf>2</inf>O<inf>3</inf> Model Catalyst during Three-Way Catalytic Reaction: An Operando X-ray Absorption Spectroscopy Study

Hiroyuki Asakura, Saburo Hosokawa, Toshiaki Ina, Kazuo Kato, Kiyofumi Nitta, Kei Uera, Tomoya Uruga, Hiroki Miura, Tetsuya Shishido, Junya Ohyama, Atsushi Satsuma, Katsutoshi Sato, Akira Yamamoto, Satoshi Hinokuma, Hiroshi Yoshida, Masato Machida, Seiji Yamazoe, Tatsuya Tsukuda, Kentaro Teramura, Tsunehiro Tanaka

Journal of the American Chemical Society Vol. 140 ( 1 ) page： 176 - 184 2018.1

Language：English Publishing type：Research paper (scientific journal)

© 2017 American Chemical Society. The dynamic behavior of Rh species in 1 wt% Rh/Al2O3 catalyst during the three-way catalytic reaction was examined using a micro gas chromatograph, a NOx meter, a quadrupole mass spectrometer, and time-resolved quick X-ray absorption spectroscopy (XAS) measurements at a public beamline for XAS, BL01B1 at SPring-8, operando. The combined data suggest different surface rearrangement behavior, random reduction processes, and autocatalytic oxidation processes of Rh species when the gas is switched from a reductive to an oxidative atmosphere and vice versa. This study demonstrates an implementation of a powerful operando XAS system for heterogeneous catalytic reactions and its importance for understanding the dynamic behavior of active metal species of catalysts.

DOI： 10.1021/jacs.7b07114

Scopus

PubMed

Reductive Conversion of 5-Hydroxymethylfurfural in Aqueous Solutions by Furan Ring Opening and Rearrangement

Ohyama Junya, Satsuma Atsushi

PRODUCTION OF BIOFUELS AND CHEMICALS WITH BIFUNCTIONAL CATALYSTS page： 159-185 2017.12

The Metal-Support Interaction Concerning the Particle Size Effect of Pd/Al2O3 on Methane Combustion

Kazumasa Murata, Yuji Mahara, Junya Ohyama, Yuta Yamamoto, Shigeo Arai, Atsushi Satsuma

ANGEWANDTE CHEMIE-INTERNATIONAL EDITION Vol. 56 ( 50 ) page： 15993 - 15997 2017.12

Language：Japanese Publishing type：Research paper (scientific journal) Publisher：WILEY-V C H VERLAG GMBH

The particle size effect of Pd nanoparticles supported on alumina with various crystalline phases on methane combustion was investigated. Pd/, -Al2O3 with weak metal-support interaction showed a volcano-shaped dependence of the catalytic activity on the size of Pd particles, and the catalytic activity of the strongly interacted Pd/-Al2O3 increased with the particle size. Based on a structural analysis of Pd nanoparticles using CO adsorption IR spectroscopy and spherical aberration-corrected scanning/transmission electron microscopy, the dependence of catalytic activity on Pd particle size and the alumina crystalline phase was due to the fraction of step sites on Pd particle surface. The difference in fraction of the step site is derived from the particle shape, which varies not only with Pd particle size but also with the strength of metal-support interaction. Therefore, this interaction perturbs the particle size effect of Pd/Al2O3 for methane combustion.

DOI： 10.1002/anie.201709124

Web of Science

Scopus

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Papers - SATSUMA, Atsushi