Ind. Eng. Chem. Res. 1998, 37, 2307-2315
2307
In Situ Real-Time Studies of Heterogeneous Catalytic Mechanisms at Ambient Pressures As Probed by Surface-Enhanced Raman and Mass Spectroscopies Christopher T. Williams,† Ho Yeung H. Chan,† Anish A. Tolia,† Michael J. Weaver,‡ and Christos G. Takoudis*,§ School of Chemical Engineering and Department of Chemistry, Purdue University, West Lafayette, Indiana 47907, and Department of Chemical Engineering, University of Illinois at Chicago, Chicago, Illinois 60607
The utility of surface-enhanced Raman spectroscopy (SERS) as an in situ adsorbate probe of heterogeneous catalytic systems at high gas pressures (here up to 1 atm) in conjunction with mass spectrometry (MS) is demonstrated for reactions on transition-metal catalysts, at temperatures up to 500 °C. This simultaneous SERS-MS approach enables the relationships between the formation of specific adsorbed species (as sensed by SERS) and reaction products (as detected by MS) to be explored on a common (≈1 s) time scale. The low-frequency (
