A new aspect of catalysis at designed surfaces: the role of gas phase molecules in surface catalytic reactions

This paper attempts to extend our previous studies on the chemical design a nd characterization of attached metal atoms at surfaces of a Nb/SiO2 cataly sts prepared by using a suitable metal-complex precursor and the elucidatio n of catalytic reaction mechanisms in a molecular scale. The paper also rep orts a new aspect of catalysis on a Co/Al2O3 catalyst which includes surfac e catalytic reactions assisted by gas phase molecules undetectable at the s urface. On the basis of this concept, one may design new catalytic systems where the reaction intermediates, stable and unreactive in vacuum, can be a ctivated or controlled by gas phase molecules in situ under catalytic react ion conditions. (C) 1999 Elsevier Science B.V. All rights reserved.