X-ray Absorption Spectroscopic Characterization of Solid Acid-base Catalysts

Abstract

Recent X-ray absorption spectroscopic studies of solid acid-base catalysts were reviewed, which have been carried out to investigate the effects of lanthanum-ion addition to alumina for improving the thermal stability, acidity generation mechanism of siliceous mesoporous silica, or state of tungsten oxide species in WO_x–ZrO₂ strong solid acid. Remarks on EXAFS analytical procedures were also discussed about possibility of coexistence of multiple phases, mismatch between radial distribution functions and Fourier transforms of EXAFS, and effects of multiple excitations in an X-ray absorption spectrum.