XAS Study of Au Supported on TiO2: Influence of Oxidation State and Particle Size on Catalytic Activity

摘要: The effect of synthesis and reaction conditions on the structure activity Au clusters supported nanocrystalline mesoporous TiO2 was investigated. X-ray absorption spectroscopy applied to correlate particle size oxidation state with several parameters, such as pH precursor solution, loading, pretreatment, support structure. study using shows that lower loadings resulted in bigger aggregates reducibility. high for different allotropic forms corresponds a fully reduced state. Furthermore, once reduced, no reoxidation occurs under conditions, even after flowing air at higher temperatures (150 300 °C). Therefore, our results indicate oxidized is not necessary activity. decreased growth, and, compared other TiO2, brookite exhibited significant agglomeration most ...