Activity Trend Origin of Ethanol Oxidative Dehydrogenation over VOx/CeO2

Supported vanadia (VOx) is a versatile catalyst for various redox  processes,  where ceria-supported VOx have  shown  to  be particularly active in oxidative dehydrogenation (ODH) of alcohols. In this  work,we  clarify  the origin  of  the volcano-shaped  ethanol  ODH activity trend for VOx/CeOx catalysts using operando quick V K-and Ce L3-edge XAS experiments performed under transient conditions.We quantitatively demonstrate  that both vanadium  and  cerium are synergistically   involved   in alcohol ODH. The   concentration   of reversible Ce4+/Ce3+species was identified as the main descriptor of the alcohol ODH activity. The  activity  drop in  the  volcano  plot, observed  at above  ca. 3  V/nm2surface  loading (ca.  30%of  VOx monolayer coverage),is related to the formation of spectator V4+and Ce3+species,  which  were identified  here for  the  first  time. These results might prove  to  be helpful for  the rational optimization of VOx/CeO2 catalysts and the refinement of the theoretical models

Contact

Dr Olga Safonova
SuperXAS beamline
Operando spectroscopy group
Swiss Light Source, Paul Scherrer Intitute
5232 Villigen-PSI, Switzerland
Telephone: +41 56 310 58 05
E-mail: olga.safonova@psi.ch

Original Publication

Activity Trend Origin of Ethanol Oxidative Dehydrogenation over VOx/CeO2

Anna Zabilska, Maxim Zabilskiy, Rob Jeremiah G. Nuguid, Adam H. Clark, Ilia I. Sadykov, Maarten Nachtegaal, Oliver Kröcher, Olga V. Safonova

Angewandte Chemie Int. Ed.,  1 March 2023
DOI:10.1002/anie.202301297