Structure of metal catalysts

Metal catalysts are technologically very important. Moreover, these materials are intriguing systems for scientific investigation. In general, metal catalysts are highly dispersed materials, i.e., materials with very high surface areas. The study of these materials with chemical probes including chemisorption and selected catalytic reactions, in conjunction with physical methods such as electron microscopy, x-ray diffraction, photoelectron spectroscopy, and extended x-ray absorption fine-structure spectroscopy, has contributed much to our knowledge of their structures. Metal catalysts considered in this article include systems consisting essentially of a single metal component (monometallic catalysts) and also bimetallic systems, this latter group including metal alloys as well as highly dispersed bimetallic clusters.