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一、引言 1978年Tauster等人发现载在TiO_2载体上的Ⅷ族贵金属在高于500℃氢气氛中还原后,吸附H_2、CO的能力大大下降,有的甚至降为零。继而又发现金属的催化性能发生了很大改变,如Rh/TiO_2上形成CH_4的比速率提高了一个数量级,而C_6H_6加氢等反应活性明显下降。Tauster等认为金属和载体发生了强相互作用(Strong Metal-Support Iinteraction,缩写为SMSI)。这是一个比较笼统的提法,它的实质是什么,最近几年展开了颇为广泛的研究和讨论。
I. INTRODUCTION Tauster et al. Found in 1978 that the ability of Group VIII noble metal supported on TiO 2 to reduce H 2 and CO greatly decreased to some extent even to zero after it was reduced in hydrogen atmosphere above 500 ℃. Subsequently, the catalytic properties of the metal have been greatly changed. For example, the formation rate of CH 4 on Rh / TiO 2 increases by an order of magnitude, whereas the reactivity of C 6 H 6 hydrogenation decreases significantly. Tauster et al. [2] considered the metal-support interaction (SMSI) as a metal-carrier interaction. This is a more general formulation. What is its essence? In recent years, there has been quite a lot of research and discussion.