Aberration‐corrected Analytical Microscopy Characterization of Double‐Supported WO₃/TiO₂/SiO₂ Solid Acid Catalysts

Abstract

Double‐supported metal oxide catalysts, in which an oxide support material with a high surface area is modified by the presence of a second metal oxide surface species added to control the distribution and activity of a third active oxide component, represent a significant challenge in terms of structural characterization. In this study the various components in a double‐supported WO3/TiO2/SiO2 catalyst system are effectively visualized by using complementary high‐angle annular dark field (HAADF) and bright field (BF) imaging within an aberration‐corrected scanning transmission electron microscope (STEM). Furthermore, if combined with chemical analysis by electron energy‐loss spectroscopy (EELS) and X‐ray energy‐dispersive spectroscopy (XEDS) within the same STEM instrument, it is possible to map out the relative spatial distribution of all the metal oxide components within the WO3/TiO2/SiO2 catalysts. By comparing the structures of a systematic set of WO3/TiO2/SiO2 samples that display high, intermediate and low activity for the methanol dehydration reaction, new insight is provided into the structure‐performance relationships that exist in this double supported catalyst system.

Restructuring Transition Metal Oxide Nanorods for 100% Selectivity in Reduction of Nitric Oxide with Carbon Monoxide

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Electron Microscopy of Solid Catalysts—Transforming from a Challenge to a Toolbox

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