Combining X-ray absorption with X-ray diffraction for the structural elucidation of catalysts

We describe how the combined XAS/XRD technique can provide powerful information on the structures of catalytically active centres. We consider some of the most industrially important catalysts, including Fe-ZSM-5, TS-1, Ti-zeolite beta, Ti-MCM-41 and determine the coordination environment in the active state. In addition, we show how EXAFS information is invaluable as a means for understanding and predicting redox catalytic properties of transition-metal-ion-substituted microporous aluminophosphates - materials which are the best inorganic systems known to date for functionalizing selectively terminal groups of an alkane molecule, in air at moderate temperatures and pressures.