摘要
以Fe2O3,Co3O4,ZrO2和ZrO2-CeO2为载体,研究了负载型Au催化剂在CO优选氧化反应中的性能,并用高分辨透射电子显微镜、X射线衍射和X射线光电子能谱等技术对催化剂进行了表征,考察了Au与载体之间的相互作用对Au电子性质的影响.结果表明,在60℃以下,Au/Fe2O3上CO能被完全氧化,且CO氧化反应选择性约为50%,而在Au/Co3O4,Au/ZrO2和Au/ZrO2-CeO2催化剂上,CO在更低的温度下才能被完全氧化.这是由于具有拉电子效应的载体(如Fe2O3和Co3O4)能使Au带有部分正电荷,从而对CO优选氧化反应具有较高的催化活性.因此,选择合适的载体或对载体进行掺杂改性,调节Au的正电荷数目,有可能进一步提高Au催化剂的催化活性.
The catalytic performance of Au/Fe2O3, Au/Co3O4, Au/ZrO2, and Au/ZrO2-CeO2 catalysts for preferential oxidation of CO （CO PROX） was investigated, and the catalysts were characterized by high resolution transmission electron microscopy, X-ray diffraction, and X-ray photoelectron spectroscopy. The effect of the interaction between Au and the supports on the electronic properties of Au was discussed. CO was totally converted at the temperature not higher than 60 ℃ over Au/Fe2O3 catalyst, and the selectivity for CO PROX was about 50% ; while the other catalysts showed worse catalytic performance. The positive inductive effect of supports （such as Fe2O3 and Co3O4） , which could make Au bearing some positive charge, was supposed to be the key factor for the catalyst activity in CO PROX. The catalyst activity could be improved by choosing or modifying the supports to get suitable positive charge of Au.
出处
《催化学报》
SCIE
CAS
CSCD
北大核心
2008年第4期361-365,共5页
