Shape Effects of Ceria Nanoparticles on the Water‒Gas Shift Performance of CuO<sub>x</sub>/CeO<sub>2</sub> Catalysts
The copper–ceria (CuO<sub>x</sub>/CeO<sub>2</sub>) system has been extensively investigated in several catalytic processes, given its distinctive properties and considerable low cost compared to noble metal-based catalysts. The fine-tuning of key parameters, e.g., the particl...
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MDPI AG
2021-06-01
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| Series: | Catalysts |
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| Online Access: | https://www.mdpi.com/2073-4344/11/6/753 |
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| author | Maria Lykaki Sofia Stefa Sónia A. C. Carabineiro Miguel A. Soria Luís M. Madeira Michalis Konsolakis |
| author_facet | Maria Lykaki Sofia Stefa Sónia A. C. Carabineiro Miguel A. Soria Luís M. Madeira Michalis Konsolakis |
| author_sort | Maria Lykaki |
| collection | DOAJ |
| description | The copper–ceria (CuO<sub>x</sub>/CeO<sub>2</sub>) system has been extensively investigated in several catalytic processes, given its distinctive properties and considerable low cost compared to noble metal-based catalysts. The fine-tuning of key parameters, e.g., the particle size and shape of individual counterparts, can significantly affect the physicochemical properties and subsequently the catalytic performance of the binary oxide. To this end, the present work focuses on the morphology effects of ceria nanoparticles, i.e., nanopolyhedra (P), nanocubes (C), and nanorods (R), on the water–gas shift (WGS) performance of CuO<sub>x</sub>/CeO<sub>2</sub> catalysts. Various characterization techniques were employed to unveil the effect of shape on the structural, redox and surface properties. According to the acquired results, the support morphology affects to a different extent the reducibility and mobility of oxygen species, following the trend: R > P > C. This consequently influences copper–ceria interactions and the stabilization of partially reduced copper species (Cu<sup>+</sup>) through the Cu<sup>2+</sup>/Cu<sup>+</sup> and Ce<sup>4+</sup>/Ce<sup>3+</sup> redox cycles. Regarding the WGS performance, bare ceria supports exhibit no activity, while the addition of copper to the different ceria nanostructures alters significantly this behaviour. The CuO<sub>x</sub>/CeO<sub>2</sub> sample of rod-like morphology demonstrates the best catalytic activity and stability, approaching the thermodynamic equilibrium conversion at 350 °C. The greater abundance in loosely bound oxygen species, oxygen vacancies and highly dispersed Cu<sup>+</sup> species can be mainly accounted for its superior catalytic performance. |
| first_indexed | 2024-03-10T10:13:26Z |
| format | Article |
| id | doaj.art-2e49396912d041b0bb4503dd6daa0e6d |
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| issn | 2073-4344 |
| language | English |
| last_indexed | 2024-03-10T10:13:26Z |
| publishDate | 2021-06-01 |
| publisher | MDPI AG |
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| series | Catalysts |
| spelling | doaj.art-2e49396912d041b0bb4503dd6daa0e6d2023-11-22T00:59:55ZengMDPI AGCatalysts2073-43442021-06-0111675310.3390/catal11060753Shape Effects of Ceria Nanoparticles on the Water‒Gas Shift Performance of CuO<sub>x</sub>/CeO<sub>2</sub> CatalystsMaria Lykaki0Sofia Stefa1Sónia A. C. Carabineiro2Miguel A. Soria3Luís M. Madeira4Michalis Konsolakis5School of Production Engineering and Management, Technical University of Crete, GR-73100 Chania, GreeceSchool of Production Engineering and Management, Technical University of Crete, GR-73100 Chania, GreeceLAQV-REQUIMTE, Department of Chemistry, NOVA School of Science and Technology, Universidade NOVA de Lisboa, 2829-516 Caparica, PortugalLEPABE–Laboratory for Process Engineering, Environment, Biotechnology and Energy, Faculty of Engineering, University of Porto, Rua Dr. Roberto Frias, 4200-465 Porto, PortugalLEPABE–Laboratory for Process Engineering, Environment, Biotechnology and Energy, Faculty of Engineering, University of Porto, Rua Dr. Roberto Frias, 4200-465 Porto, PortugalSchool of Production Engineering and Management, Technical University of Crete, GR-73100 Chania, GreeceThe copper–ceria (CuO<sub>x</sub>/CeO<sub>2</sub>) system has been extensively investigated in several catalytic processes, given its distinctive properties and considerable low cost compared to noble metal-based catalysts. The fine-tuning of key parameters, e.g., the particle size and shape of individual counterparts, can significantly affect the physicochemical properties and subsequently the catalytic performance of the binary oxide. To this end, the present work focuses on the morphology effects of ceria nanoparticles, i.e., nanopolyhedra (P), nanocubes (C), and nanorods (R), on the water–gas shift (WGS) performance of CuO<sub>x</sub>/CeO<sub>2</sub> catalysts. Various characterization techniques were employed to unveil the effect of shape on the structural, redox and surface properties. According to the acquired results, the support morphology affects to a different extent the reducibility and mobility of oxygen species, following the trend: R > P > C. This consequently influences copper–ceria interactions and the stabilization of partially reduced copper species (Cu<sup>+</sup>) through the Cu<sup>2+</sup>/Cu<sup>+</sup> and Ce<sup>4+</sup>/Ce<sup>3+</sup> redox cycles. Regarding the WGS performance, bare ceria supports exhibit no activity, while the addition of copper to the different ceria nanostructures alters significantly this behaviour. The CuO<sub>x</sub>/CeO<sub>2</sub> sample of rod-like morphology demonstrates the best catalytic activity and stability, approaching the thermodynamic equilibrium conversion at 350 °C. The greater abundance in loosely bound oxygen species, oxygen vacancies and highly dispersed Cu<sup>+</sup> species can be mainly accounted for its superior catalytic performance.https://www.mdpi.com/2073-4344/11/6/753ceria nanoparticlesCuO<sub>x</sub>/CeO<sub>2</sub> mixed oxidesshape effectswater–gas shift reaction (WGSR) |
| spellingShingle | Maria Lykaki Sofia Stefa Sónia A. C. Carabineiro Miguel A. Soria Luís M. Madeira Michalis Konsolakis Shape Effects of Ceria Nanoparticles on the Water‒Gas Shift Performance of CuO<sub>x</sub>/CeO<sub>2</sub> Catalysts Catalysts ceria nanoparticles CuO<sub>x</sub>/CeO<sub>2</sub> mixed oxides shape effects water–gas shift reaction (WGSR) |
| title | Shape Effects of Ceria Nanoparticles on the Water‒Gas Shift Performance of CuO<sub>x</sub>/CeO<sub>2</sub> Catalysts |
| title_full | Shape Effects of Ceria Nanoparticles on the Water‒Gas Shift Performance of CuO<sub>x</sub>/CeO<sub>2</sub> Catalysts |
| title_fullStr | Shape Effects of Ceria Nanoparticles on the Water‒Gas Shift Performance of CuO<sub>x</sub>/CeO<sub>2</sub> Catalysts |
| title_full_unstemmed | Shape Effects of Ceria Nanoparticles on the Water‒Gas Shift Performance of CuO<sub>x</sub>/CeO<sub>2</sub> Catalysts |
| title_short | Shape Effects of Ceria Nanoparticles on the Water‒Gas Shift Performance of CuO<sub>x</sub>/CeO<sub>2</sub> Catalysts |
| title_sort | shape effects of ceria nanoparticles on the water gas shift performance of cuo sub x sub ceo sub 2 sub catalysts |
| topic | ceria nanoparticles CuO<sub>x</sub>/CeO<sub>2</sub> mixed oxides shape effects water–gas shift reaction (WGSR) |
| url | https://www.mdpi.com/2073-4344/11/6/753 |
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