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Miran HA, Jaf ZN, Altarawneh M, Jiang ZT. An Insight into Geometries and Catalytic Applications of CeO 2 from a DFT Outlook. Molecules 2021; 26:6485. [PMID: 34770889 PMCID: PMC8588098 DOI: 10.3390/molecules26216485] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2021] [Revised: 10/19/2021] [Accepted: 10/21/2021] [Indexed: 11/18/2022] Open
Abstract
Rare earth metal oxides (REMOs) have gained considerable attention in recent years owing to their distinctive properties and potential applications in electronic devices and catalysts. Particularly, cerium dioxide (CeO2), also known as ceria, has emerged as an interesting material in a wide variety of industrial, technological, and medical applications. Ceria can be synthesized with various morphologies, including rods, cubes, wires, tubes, and spheres. This comprehensive review offers valuable perceptions into the crystal structure, fundamental properties, and reaction mechanisms that govern the well-established surface-assisted reactions over ceria. The activity, selectivity, and stability of ceria, either as a stand-alone catalyst or as supports for other metals, are frequently ascribed to its strong interactions with the adsorbates and its facile redox cycle. Doping of ceria with transition metals is a common strategy to modify the characteristics and to fine-tune its reactive properties. DFT-derived chemical mechanisms are surveyed and presented in light of pertinent experimental findings. Finally, the effect of surface termination on catalysis by ceria is also highlighted.
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Affiliation(s)
- Hussein A. Miran
- Department of Physics, College of Education for Pure Science, Ibn Al-Haitham, University of Baghdad, Baghdad 10071, Iraq;
| | - Zainab N. Jaf
- Department of Physics, College of Education for Pure Science, Ibn Al-Haitham, University of Baghdad, Baghdad 10071, Iraq;
| | - Mohammednoor Altarawneh
- Department of Chemical and Petroleum Engineering, United Arab Emirates University, Sheikh Khalifa Bin Zayed Street, Al-Ain 15551, United Arab Emirates
| | - Zhong-Tao Jiang
- Surface Analysis and Materials Engineering Research Group, College of Science, Health, Engineering and Education, Murdoch University, Murdoch, WA 6150, Australia;
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Gangwar BP, Pentyala P, Tiwari K, Biswas K, Sharma S, Deshpande PA. Dry reforming activity due to ionic Ru in La 1.99Ru 0.01O 3: the role of specific carbonates. Phys Chem Chem Phys 2019; 21:16726-16736. [PMID: 31322149 DOI: 10.1039/c9cp02337b] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Dry reforming of methane was carried out over La2-2xRu2xO3 (x = 0.005, 0.01). Substitution of just 0.5 atom% of Ru in La2O3 enhanced the activity by 20 times in terms of conversion when compared to the activity exhibited by La2O3. The oxygen storage capacity of the Ru doped sample was considerably higher than undoped La2O3, which resulted in higher conversions of CH4 and CO2. The measured conversion of CH4 and CO2 was 72 and 80%, respectively, at 850 °C. The same was merely 4% with La2O3 under the same experimental conditions. DRIFTS studies demonstrated the role of a specific type of carbonates in promoting the activity of the catalyst. DFT calculations provided the rationale behind the selection of the Ru-in-La2O3 methane dry reforming catalyst. The surface structures of the pure and Ru-substituted compounds were determined, corroborating the experimental observation of enhanced oxygen storage capacity on Ru substitution. Different active surface oxygen species were identified and their roles in improving reducibilities and improving reactivities were established. The experimentally observed surface carbonate species were also identified using calculations. The combined experiment + calculation approach proved ionic Ru in La2-2xRu2xO3 to be a novel and efficient dry reforming catalyst.
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Affiliation(s)
- Bhanu P Gangwar
- Department of Chemistry, Indian Institute of Technology Gandhinagar, Palaj, Gandhinagar, Gujarat 382355, India.
| | - Phanikumar Pentyala
- Quantum and Molecular Engineering Laboratory, Department of Chemical Engineering, Indian Institute of Technology Kharagpur, Kharagpur 721302, India.
| | - Khushubo Tiwari
- Department of Materials Science and Engineering, Indian Institute of Technology Kanpur, Kanpur 208016, India
| | - Krishanu Biswas
- Department of Materials Science and Engineering, Indian Institute of Technology Kanpur, Kanpur 208016, India
| | - Sudhanshu Sharma
- Department of Chemistry, Indian Institute of Technology Gandhinagar, Palaj, Gandhinagar, Gujarat 382355, India.
| | - Parag A Deshpande
- Quantum and Molecular Engineering Laboratory, Department of Chemical Engineering, Indian Institute of Technology Kharagpur, Kharagpur 721302, India.
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Amos RIJ, Heinroth F, Chan B, Ward AJ, Zheng S, Haynes BS, Easton CJ, Masters AF, Maschmeyer T, Radom L. Hydrogen from Formic Acid via Its Selective Disproportionation over Nanodomain-Modified Zeolites. ACS Catal 2015. [DOI: 10.1021/cs501677b] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Affiliation(s)
- Ruth I. J. Amos
- School
of Chemistry, The University of Sydney, Sydney, New South Wales 2006, Australia
- CSIRO Energy Transformed Cluster
on Biofuels ⊥ARC Centre of Excellence for Free
Radical Chemistry and Biotechnology ∥Research School of Chemistry, Australian National University, Canberra, Australian Capital Territory 0200, Australia
- School of Chemical and Biomolecular Engineering, The University of Sydney, Sydney, New South Wales 2006, Australia
| | - Falk Heinroth
- School
of Chemistry, The University of Sydney, Sydney, New South Wales 2006, Australia
- CSIRO Energy Transformed Cluster
on Biofuels ⊥ARC Centre of Excellence for Free
Radical Chemistry and Biotechnology ∥Research School of Chemistry, Australian National University, Canberra, Australian Capital Territory 0200, Australia
- School of Chemical and Biomolecular Engineering, The University of Sydney, Sydney, New South Wales 2006, Australia
| | - Bun Chan
- School
of Chemistry, The University of Sydney, Sydney, New South Wales 2006, Australia
- CSIRO Energy Transformed Cluster
on Biofuels ⊥ARC Centre of Excellence for Free
Radical Chemistry and Biotechnology ∥Research School of Chemistry, Australian National University, Canberra, Australian Capital Territory 0200, Australia
- School of Chemical and Biomolecular Engineering, The University of Sydney, Sydney, New South Wales 2006, Australia
| | - Antony J. Ward
- School
of Chemistry, The University of Sydney, Sydney, New South Wales 2006, Australia
- CSIRO Energy Transformed Cluster
on Biofuels ⊥ARC Centre of Excellence for Free
Radical Chemistry and Biotechnology ∥Research School of Chemistry, Australian National University, Canberra, Australian Capital Territory 0200, Australia
- School of Chemical and Biomolecular Engineering, The University of Sydney, Sydney, New South Wales 2006, Australia
| | - Sisi Zheng
- School
of Chemistry, The University of Sydney, Sydney, New South Wales 2006, Australia
- CSIRO Energy Transformed Cluster
on Biofuels ⊥ARC Centre of Excellence for Free
Radical Chemistry and Biotechnology ∥Research School of Chemistry, Australian National University, Canberra, Australian Capital Territory 0200, Australia
- School of Chemical and Biomolecular Engineering, The University of Sydney, Sydney, New South Wales 2006, Australia
| | - Brian S. Haynes
- School
of Chemistry, The University of Sydney, Sydney, New South Wales 2006, Australia
- CSIRO Energy Transformed Cluster
on Biofuels ⊥ARC Centre of Excellence for Free
Radical Chemistry and Biotechnology ∥Research School of Chemistry, Australian National University, Canberra, Australian Capital Territory 0200, Australia
- School of Chemical and Biomolecular Engineering, The University of Sydney, Sydney, New South Wales 2006, Australia
| | - Christopher J. Easton
- School
of Chemistry, The University of Sydney, Sydney, New South Wales 2006, Australia
- CSIRO Energy Transformed Cluster
on Biofuels ⊥ARC Centre of Excellence for Free
Radical Chemistry and Biotechnology ∥Research School of Chemistry, Australian National University, Canberra, Australian Capital Territory 0200, Australia
- School of Chemical and Biomolecular Engineering, The University of Sydney, Sydney, New South Wales 2006, Australia
| | - Anthony F. Masters
- School
of Chemistry, The University of Sydney, Sydney, New South Wales 2006, Australia
- CSIRO Energy Transformed Cluster
on Biofuels ⊥ARC Centre of Excellence for Free
Radical Chemistry and Biotechnology ∥Research School of Chemistry, Australian National University, Canberra, Australian Capital Territory 0200, Australia
- School of Chemical and Biomolecular Engineering, The University of Sydney, Sydney, New South Wales 2006, Australia
| | - Thomas Maschmeyer
- School
of Chemistry, The University of Sydney, Sydney, New South Wales 2006, Australia
- CSIRO Energy Transformed Cluster
on Biofuels ⊥ARC Centre of Excellence for Free
Radical Chemistry and Biotechnology ∥Research School of Chemistry, Australian National University, Canberra, Australian Capital Territory 0200, Australia
- School of Chemical and Biomolecular Engineering, The University of Sydney, Sydney, New South Wales 2006, Australia
| | - Leo Radom
- School
of Chemistry, The University of Sydney, Sydney, New South Wales 2006, Australia
- CSIRO Energy Transformed Cluster
on Biofuels ⊥ARC Centre of Excellence for Free
Radical Chemistry and Biotechnology ∥Research School of Chemistry, Australian National University, Canberra, Australian Capital Territory 0200, Australia
- School of Chemical and Biomolecular Engineering, The University of Sydney, Sydney, New South Wales 2006, Australia
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Pidko EA, Xu J, Mojet BL, Lefferts L, Subbotina IR, Kazansky VB, van Santen RA. Interplay of Bonding and Geometry of the Adsorption Complexes of Light Alkanes within Cationic Faujasites. Combined Spectroscopic and Computational Study. J Phys Chem B 2006; 110:22618-27. [PMID: 17092009 DOI: 10.1021/jp0634757] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
A FT-IR spectroscopic study of methane, ethane, and propane adsorption on magnesium and calcium forms of zeolite Y reveals different vibrational properties of the adsorbed molecules depending on the exchanged cation. This is attributed to different adsorption conformations of the hydrocarbons. Two-fold eta(2) coordination of light alkanes is realized for MgY, whereas in case of CaY zeolite quite different adsorption modes are found, involving more C-H bonds in the interaction with the cation. The topological analysis of the electron density distribution function of the adsorption complexes shows that when a hydrocarbon coordinates to the exchanged Mg(2+) ions, van der Waals bonds between H atoms of the alkane and basic zeolitic oxygens significantly contribute to the overall adsorption energy, whereas in case of CaY zeolite such interactions play only an indirect role. It is found that, due to the much smaller ionic radius of the Mg(2+) ion as compared to that of Ca(2+), the former ions are significantly shielded with the surrounding oxygens of the zeolitic cation site. This results in a small electrostatic contribution to the stabilization of the adsorbed molecules. In contrast, for CaY zeolite the stabilization of alkanes in the electrostatic field of the partially shielded Ca(2+) cation significantly contributes to the adsorption energy. This is in agreement with the experimentally observed lower overall absorption of C-H stretching vibrations of alkanes loaded to MgY as compared to those for CaY zeolite. The preferred conformation of the adsorbed alkanes is controlled by the bonding within the adsorption complexes that, in turn, strongly depends on the size and location of the cations in the zeolite cavity.
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Affiliation(s)
- Evgeny A Pidko
- Schuit Institute of Catalysis, Eindhoven University of Technology, P.O. Box 513, NL-5600 MB Eindhoven, The Netherlands.
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