Water–gas shift reaction over gold nanoparticles dispersed on nanostructured CeO x–TiO 2(110) surfaces: Effects of high ceria coverage
We used scanning tunnelling microscopy to study the morphology of an overlayer of ceria in contact with a TiO 2(110) substrate. Two types of domains were observed after ceria deposition. An ordered ceria film covered half of the surface and high-resolution imaging suggested a near-c(6 × 2) relationship to the underlying TiO 2(110)-(1 × 1). For the other half of the surface, it comprised CeO x nanoparticles and reconstructed TiOx supported on TiO 2(110)-(1 × 1). Exposure to a small amount of gold resulted in the formation of isolated gold atoms and small clusters on the ordered ceria film and TiO 2(110)-(1 × 1) areas, which exhibited significant sintering at 500 K and showed strong interaction between the sintered gold clusters and the domain boundaries of the ceria film. The Au/CeO x/TiO 2(110) model system proved to be a good catalyst for the water–gas shift (WGS) exhibiting much higher turnover frequencies (TOFs) than Cu(111) and Pt(111) benchmarks, or the individual Au/TiO 2(110) and Au/CeO 2(111) systems. Finally, for Au/CeO x/TiO 2(110) catalysts, there was a decrease in catalytic activity with increasing ceria coverage that correlates with a reduction in the concentration of Ce 3 + formed during WGS reaction conditions.
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- Brookhaven National Lab. (BNL), Upton, NY (United States)
- Central Univ. of Venezuela, Caracas (Venezuela)
- Publication Date:
- Report Number(s):
- BNL-112519-2016-JA; BNL-113208-2016-JA
Journal ID: ISSN 0039-6028; R&D Project: CO009; KC0302010
- Grant/Contract Number:
- SC00112704; SC0012704
- Type:
- Accepted Manuscript
- Journal Name:
- Surface Science
- Additional Journal Information:
- Journal Volume: 650; Journal Issue: C; Journal ID: ISSN 0039-6028
- Publisher:
- Elsevier
- Research Org:
- Brookhaven National Laboratory (BNL), Upton, NY (United States)
- Sponsoring Org:
- USDOE Office of Science (SC), Basic Energy Sciences (BES) (SC-22)
- Country of Publication:
- United States
- Language:
- English
- Subject:
- 37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY; STM; TiO2 (110); CeO2; gold; water-gas shift; TiO2(110); water–gas shift
- OSTI Identifier:
- 1303023
- Alternate Identifier(s):
- OSTI ID: 1333203; OSTI ID: 1373613
- Free Publicly Accessible Full Text
- Accepted Manuscript (Publisher)
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Accepted Manuscript (DOE)
- Publisher's Version of Record
- https://doi.org/10.1016/j.susc.2015.10.002