An Investigation into Phosphate-Doped Au/Alumina for Low Temperature CO Oxidation

The physicochemical nature of phosphate entities incorporated into the alumina substrate and their effects on the catalytic activity and antiaging ability of corresponding Au catalysts for low temperature CO oxidation have been investigated. The addition of phosphorus mainly depresses the catalytic activity and improves the thermal stability of corresponding Au catalysts. However, the catalytic activity is surprisingly recovered with a further improvement in thermal stability of the Au catalyst as calcination temperature of the phosphate-doped Al2O3 increased. Infrared spectroscopy, X-ray photoelectron spectrometery, X-ray diffraction, and N-2 adsorption-desorption isotherm evidenced the important structural and chemical change of P-modified Au catalysts upon calcination temperature. The influence by textural and electronic changes in the catalytic performance of corresponding Au-based catalysts is discussed.