Structure characterization of WO3/ZrO2 catalysts by Raman spectroscopy

Biying Zhao, Xianping Xu, Jinming Gao, Qiang Fu, Youqi Tang

Research output: Contribution to journalArticle

50 Citations (Scopus)

Abstract

WO3/ZrO2 catalysts prepared by different methods are distinct in their catalytic behaviour. In this work, WO3/ZrO2 catalysts prepared by impregnating Zr(OH)4 and crystallized ZrO2 and then calcining at selected temperatures were characterized by means of qualitative and quantitative Raman spectroscopy. The results showed that ZrO2 in WO3/ZrO2 obtained from crystallized ZrO2 (referred to as WZ) is monoclinic, whereas ZrO2 in WO3/ZrO2 obtained from Zr(OH)4 (referred to as WZH) is in a metastable tetragonal phase as long as the WO3 content is high enough. In both WZ and WZH, WO3 is dispersed on ZrO2 as a monolayer, and the dispersion capacity per 100 m2 of ZrO2 is in good agreement with that estimated from the close-packed monolayer model. However, since the specific surface areas of WZH samples are larger than those of WZ samples, the dispersion capacity per gram of ZrO2 of WZH is larger than that of WZ. A chemical reaction may occur between WO3 and the surface of Zr(OH)4 (or tetragonal ZrO2) at high temperature, and then some superacid sites are created on the surface of the WZH sample.

Original languageEnglish (US)
Pages (from-to)549-554
Number of pages6
JournalJournal of Raman Spectroscopy
Volume27
Issue number7
StatePublished - Jul 1996

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Raman spectroscopy
Monolayers
Catalysts
Metastable phases
Specific surface area
Chemical reactions
Temperature

ASJC Scopus subject areas

  • Spectroscopy

Cite this

Structure characterization of WO3/ZrO2 catalysts by Raman spectroscopy. / Zhao, Biying; Xu, Xianping; Gao, Jinming; Fu, Qiang; Tang, Youqi.

In: Journal of Raman Spectroscopy, Vol. 27, No. 7, 07.1996, p. 549-554.

Research output: Contribution to journalArticle

Zhao, B, Xu, X, Gao, J, Fu, Q & Tang, Y 1996, 'Structure characterization of WO3/ZrO2 catalysts by Raman spectroscopy', Journal of Raman Spectroscopy, vol. 27, no. 7, pp. 549-554.
Zhao, Biying ; Xu, Xianping ; Gao, Jinming ; Fu, Qiang ; Tang, Youqi. / Structure characterization of WO3/ZrO2 catalysts by Raman spectroscopy. In: Journal of Raman Spectroscopy. 1996 ; Vol. 27, No. 7. pp. 549-554.
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