摘要
随着先进的近代分析方法的发展,有关负载型金属催化剂表面性质的研究愈来愈深入.人们发现,金属与载体间存在着某些微妙的关系.其中最让人们感到困惑和兴趣的是金属和载体间的强相互作用(SISM).Vannice等发现在CO氢化反应中,经450℃还原后的Ni/TiO_2催化剂,显示出比同样条件下处理的 Ni/Al_2O_3,Ni/SiO_2等有更高的活性,并归因于Ni和TiO_2之间的SISM现象.我们在研究不同温度还原Ni/TiO_2催化剂的吸附及催化性能时发现,即使很容易产生SISM现象的TiO_2载体。
Surface properties and CO adsorption states on Ni/TiO2 catalyst reduced at different temperatures have been determined by adsorption of H2 and CO, and infrared spectroscopy. It was showed that Ni/TiO2 [catalyst reduced at 723 K was in the 'SISM' state. The behavior of the Ni/TiO2 catalysts was probably concerned in the CO adsorption state (iso-bridge form) on Ni/TiO2 surface observed at 1969 cm-1 in IR spectrum.