The ineluctable need for in situ methods of characterising solid catalysts as a prerequisite to engineering active sites

Ultimate success in the design of solid oxide catalysts as well as other covalently bonded or heterogenised organometallic catalysts predicates knowledge of precisely what structure it is that has to be targetted. This, in turn, demands the greatest possible precision in determining, under operating conditions, the structure of the catalyst in general and of the active site in particular. Combined Xray absorption spectroscopy and X-ray diffraction are ideal tools for such in situ investigations. Examples of such studies and of engineered catalysts, the structure of which have been determined in atomic detail, are given.