5 years ago

Acetylene and Ethylene Adsorption on a β-Mo2C(100) Surface: A Periodic DFT Study on the Role of C- and Mo-Terminations for Bonding and Hydrogenation Reactions

Acetylene and Ethylene Adsorption on a β-Mo2C(100) Surface: A Periodic DFT Study on the Role of C- and Mo-Terminations for Bonding and Hydrogenation Reactions
Andres Moreno, Elizabeth Florez, Carlos Jimenez-Orozco, José A. Rodriguez, Ping Liu
Mo2C catalysts are widely used in hydrogenation reactions; however, the role of the C and Mo terminations in these catalysts is not clear. Understanding the binding of adsorbates is key for explaining the activity of Mo2C. The adsorption of acetylene and ethylene, probe molecules representing alkynes and olefins, respectively, was studied on a β-Mo2C(100) surface with C and Mo terminations using calculations based on periodic density functional theory. Moreover, the role of the C/Mo molar ratio was investigated to compare the catalytic potential of cubic (δ-MoC) and orthorhombic (β-Mo2C) surfaces. The geometry and electronic properties of the clean δ-MoC(001) and β-Mo2C(100) surfaces have a strong influence on the binding of unsaturated hydrocarbons. The adsorption of ethylene is weaker than that of acetylene on the surfaces of the cubic and orthorhombic systems; adsorption of the hydrocarbons was stronger on β-Mo2C(100) than on δ-MoC(001). The C termination in β-Mo2C(100) actively participates in both acetylene and ethylene adsorption and is not merely a spectator. The results of this work suggest that the β-Mo2C(100)-C surface could be the one responsible for the catalytic activity during the hydrogenation of unsaturated C≡C and C═C bonds, while the Mo-terminated surface could be poisoned or transformed by the strong adsorption of C and CHx fragments.

Publisher URL: http://dx.doi.org/10.1021/acs.jpcc.7b05442

DOI: 10.1021/acs.jpcc.7b05442

You might also like
Discover & Discuss Important Research

Keeping up-to-date with research can feel impossible, with papers being published faster than you'll ever be able to read them. That's where Researcher comes in: we're simplifying discovery and making important discussions happen. With over 19,000 sources, including peer-reviewed journals, preprints, blogs, universities, podcasts and Live events across 10 research areas, you'll never miss what's important to you. It's like social media, but better. Oh, and we should mention - it's free.

  • Download from Google Play
  • Download from App Store
  • Download from AppInChina

Researcher displays publicly available abstracts and doesn’t host any full article content. If the content is open access, we will direct clicks from the abstracts to the publisher website and display the PDF copy on our platform. Clicks to view the full text will be directed to the publisher website, where only users with subscriptions or access through their institution are able to view the full article.