Jump to main content
Jump to site search

Issue 31, 2019
Previous Article Next Article

Superior electrocatalytic hydrogen evolution at engineered non-stoichiometric two-dimensional transition metal dichalcogenide edges

Author affiliations

Abstract

Two-dimensional transition metal dichalcogenide (TMDC) edges show activity for the catalytic hydrogen evolution reaction (HER), but further improvements require extrinsic doping, usually performed in an Edisonian manner. Herein we investigate if tuning the non-stoichiometric degree of the edges itself can improve HER activities. Using first-principles density functional theory (DFT), we study six non-stoichiometric MoSe2 edges that have been recently synthesized under a scanning transmission electron microscope (STEM). We find that non-stoichiometric edges can have near optimal HER activity over conventional stoichiometric edges. More excitingly, we find a strong linear correlation between Bader charges on H and the Gibbs free energy of hydrogen adsorption (ΔGH) at these edges, providing a design principle for discovering better HER catalytic edges. In general, HER activity is not only influenced by the formation of H–Se/Mo chemical bonds as previously thought, but also by geometric reconstructions and charge redistribution. Our predictions open the door for engineering non-stoichiometric TMDC edges for superior HER activity.

Graphical abstract: Superior electrocatalytic hydrogen evolution at engineered non-stoichiometric two-dimensional transition metal dichalcogenide edges

Back to tab navigation

Supplementary files

Publication details

The article was received on 24 May 2019, accepted on 09 Jul 2019 and first published on 10 Jul 2019


Article type: Paper
DOI: 10.1039/C9TA05546K
J. Mater. Chem. A, 2019,7, 18357-18364

  •   Request permissions

    Superior electrocatalytic hydrogen evolution at engineered non-stoichiometric two-dimensional transition metal dichalcogenide edges

    G. Hu, V. Fung, X. Sang, R. R. Unocic and P. Ganesh, J. Mater. Chem. A, 2019, 7, 18357
    DOI: 10.1039/C9TA05546K

Search articles by author

Spotlight

Advertisements