Abstract Reducible oxides are widely used catalyst supports that can increase oxidation reaction rates by transferring lattice oxygen at the metal-support interface. There are many outstanding questions regarding the atomic-scale dynamic meta-stability (i.e., fluxional behavior) of the interface during catalysis. Here, we employ aberration-correctedoperandoelectron microscopy to visualize the structural dynamics occurring at and near Pt/CeO2interfaces during CO oxidation. We show that the catalytic turnover frequency correlates with fluxional behavior that (a) destabilizes the supported Pt particle, (b) marks an enhanced rate of oxygen vacancy creation and annihilation, and (c) leads to increased strain and reduction in the CeO2support surface. Overall, the results implicate the interfacial Pt-O-Ce bonds anchoring the Pt to the support as being involved also in the catalytically-driven oxygen transfer process, and they suggest that oxygen reduction takes place on the highly reduced CeO2surface before migrating to the interfacial perimeter for reaction with CO.
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Recent Progress on Cerium Oxide‐Based Nanostructures for Energy and Environmental Applications
Cerium oxide (CeO2) photo/electrocatalysts for energy storage and environmental applications have attracted considerable interest because of stable crystal structure, low toxicity/cost, superior chemical stability, stable redox (Ce3+/Ce4+) pairs, abundant oxygen defects, and capablility for intense interaction with other materials. However, the wide bandgap and poor conductivity lower the CeO2photo/electrocatalytic and energy storage performances. To overcome these limitations, various modification strategies (tuning morphology, doping or loading of metal nanoparticles, and heterostructures) have been applied for the improvement of photocatalytic (removal of organic contaminants from water/wastewater and H2production and CO2reduction reactions) efficiency, electrocatalytic (hydrogen/oxygen evolution reactions and CO2reduction reactions), and energy storage performances (supercapacitor) of CeO2‐based materials. Herein, the recent progress of CeO2‐based materials for electro(photo)catalysis and energy storage applications has been discussed. The challenges and possible direction of CeO2‐based materials for electro(photo)catalysis and energy storage applications have been emphasized. Furthermore, this comprehensive review is expected to advance the design of CeO2‐based materials and their applications in electro(photo)catalysis and energy.
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- Award ID(s):
- 2100710
- PAR ID:
- 10639992
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Advanced Energy and Sustainability Research
- Volume:
- 6
- Issue:
- 10
- ISSN:
- 2699-9412
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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