Synchrotron powder X-ray diffraction (PXRD) was applied to the structural characterization of microporous and mesoporous materials as well as their supported metal catalysts. Advantages of synchrotron X-ray powder diffraction are illustrated by the detection of the MFI crystalline phase on the non-smooth surface of a microporous MFI film supported on the inner wall of a ceramic hollow tube, and of the formation of Au and Pt nano-particles in powdery mesoporous materials. (C) 2004 Elsevier B.V. All rights reserved.