skip to main content

SciTech ConnectSciTech Connect

Title: Uniform 2 nm gold nanoparticles supported on iron oxides as active catalysts for CO oxidation reaction: Structure-activity relationship

Uniform Au nanoparticles (~2 nm) with narrow size-distribution (standard deviation: 0.5–0.6 nm) supported on both hydroxylated (Fe_OH) and dehydrated iron oxide (Fe_O) have been prepared by either deposition-precipitation (DP) or colloidal-deposition (CD) methods. Different structural and textural characterizations were applied to the dried, calcined and used gold-iron oxide samples. The transmission electron microscopy (TEM) and high-resolution TEM (HRTEM) described the high homogeneity in the supported Au nanoparticles. The ex-situ and in-situ X-ray absorption fine structure (XAFS) characterization monitored the electronic and short-range local structure of active gold species. The synchrotron-based in-situ X-ray diffraction (XRD), together with the corresponding temperature-programmed reduction by hydrogen (H₂-TPR), indicated a structural evolution of the iron-oxide supports, correlating to their reducibility. An inverse order of catalytic activity between DP (Au/Fe_OH < Au/Fe_O) and CD (Au/Fe_OH > Au/Fe_O) was observed. Effective gold-support interaction results in a high activity for gold nanoparticles, locally generated by the sintering of dispersed Au atoms on the oxide support in the DP synthesis, while a hydroxylated surface favors the reactivity of externally introduced Au nanoparticles on Fe_OH support for the CD approach. This work reveals why differences in the synthetic protocol translate to differences in the catalytic performance of Au/FeOx catalysts withmore » very similar structural characteristics in CO oxidation.« less
 [1] ;  [2] ;  [3] ;  [1] ;  [4] ;  [4] ;  [2] ;  [4] ;  [2] ;  [1] ;  [1] ;  [3]
  1. Shandong Univ., Jinan (China)
  2. Brookhaven National Lab. (BNL), Upton, NY (United States)
  3. Max-Planck Institut fur Kohlenforschung (Germany)
  4. Chinese Academy of Sciences (CAS), Beijing (China)
Publication Date:
OSTI Identifier:
Report Number(s):
Journal ID: ISSN 2040-3364; NANOHL; R&D Project: CO009; KC0302010
Grant/Contract Number:
Accepted Manuscript
Journal Name:
Additional Journal Information:
Journal Volume: 7; Journal Issue: 11; Journal ID: ISSN 2040-3364
Royal Society of Chemistry
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
37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY gold catalyst; iron oxide; CO oxidation; in-situ x-ray technique; metal-support interaction