Structure-function relationship for CO2 methanation over ceria supported Rh and Ni catalysts under atmospheric pressure conditions
Journal article, 2019
In situ structural and chemical state characterization of Rh/CeO 2 and Ni/CeO 2 catalysts during atmospheric pressure CO 2 methanation has been performed by a combined array of time-resolved analytical techniques including ambient-pressure X-ray photoelectron spectroscopy, high-energy X-ray diffraction and diffuse reflectance infrared Fourier transform spectroscopy. The ceria phase is partially reduced during the CO 2 methanation and in particular Ce 3+ species seem to facilitate activation of CO 2 molecules. The activated CO 2 molecules then react with atomic hydrogen provided from H 2 dissociation on Rh and Ni sites to form formate species. For the most active catalyst (Rh/CeO 2 ), transmission electron microscopy measurements show that the Rh nanoparticles are small (average 4 nm, but with a long tail towards smaller particles) due to a strong interaction between Rh particles and the ceria phase. In contrast, larger nanoparticles were observed for the Ni/CeO 2 catalyst (average 6 nm, with no crystallites below 5 nm found), suggesting a weaker interaction with the ceria phase. The higher selectivity towards methane of Rh/CeO 2 is proposed to be due to the stronger metal-support interaction.
Author
Natalia Mihaela Martin
Chalmers, Chemistry and Chemical Engineering, Applied Chemistry
Competence Centre for Catalysis (KCK)
Felix Hemmingsson
Competence Centre for Catalysis (KCK)
Chalmers, Chemistry and Chemical Engineering, Applied Chemistry
Andreas Schaefer
Chalmers, Chemistry and Chemical Engineering, Applied Chemistry
Competence Centre for Catalysis (KCK)
Martin Ek
Lund University
L. R. Merte
Malmö university
Uta Hejral
Lund University
Johan Gustafsson
Lund University
Magnus Skoglundh
Chalmers, Chemistry and Chemical Engineering, Applied Chemistry
Ann Christin Dippel
Deutsches Elektronen-Synchrotron (DESY)
Olof Gutowski
Deutsches Elektronen-Synchrotron (DESY)
Matthias Bauer
Padernborn University
Per-Anders Carlsson
Chalmers, Chemistry and Chemical Engineering, Applied Chemistry
Competence Centre for Catalysis (KCK)
Catalysis Science and Technology
2044-4753 (ISSN) 2044-4761 (eISSN)
Vol. 9 7 1644-1653Atomistic Design of Catalysts
Knut and Alice Wallenberg Foundation (KAW2015.0058), 2016-01-07 -- 2021-06-30.
Time-resolved in situ methods for design of catalytic sites within sustainable chemistry
Swedish Research Council (VR) (2013-567), 2013-01-01 -- 2016-12-31.
Synergistic development of X-ray techniques and applicable thin oxides for sustainable chemistry
Swedish Research Council (VR) (2017-06709), 2018-04-04 -- 2021-12-31.
Driving Forces
Sustainable development
Areas of Advance
Energy
Materials Science
Subject Categories
Materials Chemistry
DOI
10.1039/C8CY02097C