English
 
Help Privacy Policy Disclaimer
  Advanced SearchBrowse

Item

ITEM ACTIONSEXPORT

Released

Journal Article

Uniform 2 nm gold nanoparticles supported on iron oxides as active catalysts for CO oxidation reaction: structure–activity relationship

MPS-Authors
/persons/resource/persons132875

Gu,  Dong
Research Department Schüth, Max-Planck-Institut für Kohlenforschung, Max Planck Society;

/persons/resource/persons58985

Schüth,  Ferdi
Research Department Schüth, Max-Planck-Institut für Kohlenforschung, Max Planck Society;

External Resource
No external resources are shared
Fulltext (public)
There are no public fulltexts stored in PuRe
Supplementary Material (public)
There is no public supplementary material available
Citation

Guo, Y., Gu, D., Jin, Z., Du, P.-P., Si, R., Tao, J., et al. (2015). Uniform 2 nm gold nanoparticles supported on iron oxides as active catalysts for CO oxidation reaction: structure–activity relationship. Nanoscale, 7(11), 4920-4928. doi:10.1039/C4NR06967F.


Cite as: http://hdl.handle.net/11858/00-001M-0000-0025-09A5-C
Abstract
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. Transmission electron microscopy (TEM) and high-resolution TEM (HRTEM) showed 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 with very similar structural characteristics in CO oxidation.