Gold Iron Oxide Catalyst for CO Oxidation: Effect of Support Structure
Gold iron oxide (Au/FeOx) is one of the highly active catalysts for CO oxidation, and is also a typical system for the study of the chemistry of gold catalysis. In this work, two different types of iron oxide supports, i.e. hydroxylated (Fe_OH) and dehydrated iron oxide (Fe_O) have been used for the deposition of gold via a deposition precipitation (DP) method. The structure of iron oxide has been tuned by either selecting precipitated pH of 6.7 11.2 for Fe_OH or changing calcination temperature of from 200 to 600 degC for Fe_O. Then, 1 wt. Au catalysts on these iron oxide supports were measured for low temperature CO oxidation reaction. Both fresh and used samples have been characterized by multiple techniques including transmission electron microscopy (TEM) and high resolution TEM (HRTEM) X ray diffraction (XRD) X ray photoelectron spectroscopy (XPS) X ray absorption near edge structure (XANES) and temperature programmed reduction by hydrogen (H2 TPR) It has been demonstrated that the surface properties of the iron oxide support, as well as the metal support interaction, plays crucial roles on the performance of Au/FeOx catalysts in CO oxidation.