Quantitative Effect of Zr Content on the Structure and Water–Gas Shift Reaction Activities of Gold Supported on Ceria–Zirconia.

Song, Li; Zhu, Longfeng; Li, Lei

Effect of Zr content on the structure and water–gas shift reaction catalytic activities of Au-CeO2-ZrO2 catalysts were quantitatively analyzed in detail. For the low ZrO2 content (0–15 wt. %), the Ce-Zr-O solid solutions were formed through the substitutional incorporation of Zr cations into CeO2 lattice, resulting in the contraction of cell parameters <italic>a</italic> and <italic>d</italic>-spacing (i.e., lattice distortion) and the increase of microstrain and oxygen vacancies. Quantitatively, the enhanced WGS activities have good linear correlation with the cell parameters <italic>a</italic>, microstrain, Raman shift and oxygen vacancies. Whereas, for the rich-zirconia (45 wt. %) sample, Au-CeZr-45 has some isolated <italic>t</italic>-ZrO2 and fluorite CeO2 instead of solid solution. The isolated <italic>t</italic>-ZrO2 crystallites block the contact between Au and CeO2, resulting in the agglomeration of gold clusters and, as a consequence, poor WGS activity of Au-CeZr-45 catalyst.

WATER gas shift reactions; ZIRCONIUM catalysts; ZIRCONIUM oxide; CERIUM oxides; QUANTITATIVE chemical analysis

Crystals (2073-4352), 2018, Vol 8, Issue 7, p261

2073-4352

Academic Journal

10.3390/cryst8070261