Abstract: | This paper attempts to review recent work on in-situ characterizations of metals and metal oxides supported on oxide surfaces relevant to oxide catalysis. The active well-defined surfaces can provide novel information on the key issues in catalytic research such as the structure, composition and distribution of active sites, ensembles and phases, behavior of adsorbed active species, electronic property participating in catalysis, etc., which are well characterized by recent in-situ spectroscopy and also by traditional spectroscopy. |