Carbon-supported Pt during aqueous phenol hydrogenation with and without applied electrical potential: X-ray absorption and theoretical studies of structure and adsorbates

Nirala Singh, Manh Thuong Nguyen, David C. Cantu, B. Layla Mehdi, Nigel D. Browning, John L. Fulton, Jian Zheng, Mahalingam Balasubramanian, Oliver Y. Gutiérrez, Vassiliki Alexandra Glezakou, Roger Rousseau, Niranjan Govind, Donald M. Camaioni, Charles T. Campbell, Johannes A. Lercher

Research output: Contribution to journalArticle

17 Citations (Scopus)

Abstract

Adsorbed hydrogen and phenol on Pt nanoparticles during (electro)catalytic hydrogenation are explored by combining X-ray absorption spectroscopy and ab initio simulations. Direct evidence for two types of Pt-C bonds at the surface of the metal particles detected by X-ray absorption spectroscopy suggest strong bonding between metal and the carbon support as well as adsorption of phenol nearly parallel to the surface. Hydrogen and phenol compete for accessible Pt sites. The surface concentrations are compatible with the proposal that atomic hydrogen and chemisorbed phenol are the species reacting in the rate-determining step of hydrogenation in the presence and absence of an external cathodic potential. During electrocatalytic hydrogenation the external electric potential controls the concentration of species on the surface, but does not impose structural or electronic property changes of the Pt compared to Pt particles in presence of hydrogen gas. Increasing reaction rates with increasing cathodic potential are attributed to the increase in chemical potential of adsorbed H.

Original languageEnglish
Pages (from-to)8-19
Number of pages12
JournalJournal of Catalysis
Volume368
DOIs
Publication statusPublished - Dec 2018

Keywords

  • Electrocatalysis
  • Hydrogenation
  • X-ray absorption spectroscopy

ASJC Scopus subject areas

  • Catalysis
  • Physical and Theoretical Chemistry

Fingerprint Dive into the research topics of 'Carbon-supported Pt during aqueous phenol hydrogenation with and without applied electrical potential: X-ray absorption and theoretical studies of structure and adsorbates'. Together they form a unique fingerprint.

  • Cite this

    Singh, N., Nguyen, M. T., Cantu, D. C., Mehdi, B. L., Browning, N. D., Fulton, J. L., Zheng, J., Balasubramanian, M., Gutiérrez, O. Y., Glezakou, V. A., Rousseau, R., Govind, N., Camaioni, D. M., Campbell, C. T., & Lercher, J. A. (2018). Carbon-supported Pt during aqueous phenol hydrogenation with and without applied electrical potential: X-ray absorption and theoretical studies of structure and adsorbates. Journal of Catalysis, 368, 8-19. https://doi.org/10.1016/j.jcat.2018.09.021