Carboxyl intermediate formation via an in situ-generated metastable active site during water-gas shift catalysis

  title={Carboxyl intermediate formation via an in situ-generated metastable active site during water-gas shift catalysis},
  author={Nicholas C. Nelson and Manh‐Thuong Nguyen and Vassiliki‐Alexandra Glezakou and Roger Rousseau and J{\'a}nos Szanyi},
  journal={Nature Catalysis},
Definitive experimental proof for catalytic pathways and active sites during the low-temperature water-gas shift reaction remains elusive. Herein, we combine spectroscopic, kinetic and computational analyses to address the decades-long mechanistic controversy by studying the reverse water-gas shift over Pd/Al2O3. Isotopic transient kinetic analysis established the minor role of the formate intermediate, whereas hydrogen titration experiments confirmed the intermediacy of carboxyl. The ability… 
29 Citations
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