Abstract
Atomically precise metal nanoclusters have recently emerged as a novel class of catalysts for the hydrogen evolution reaction. From first-principles density functional theory, we show that the eight coordinatively unsaturated (cus) Au atoms in the Au22(L8)6 cluster [L8 = 1,8-bis(diphenylphosphino) octane] can adsorb H stronger than Pt, thereby being a potentially promising catalyst for the hydrogen evolution reaction (HER). We find that up to six H atoms can adsorb onto the Au22(L8)6 cluster and they have close-to-zero Gibbs free adsorption energies (ΔGH). From the HOMO-LUMO gaps, frontier orbitals, and Bader charge analysis, we conclude that H behaves as a hydride or electron-withdrawing ligand in the Au22(L8)6 clusters, in contrast to the metallic H in thiolate-protected Au nanoclusters. Our study demonstrates that ligand-protected Au clusters with cus Au sites will be the most promising candidates for realizing Au-H nanoclusters and can act as excellent electrocatalysts for the HER.
| Original language | English |
|---|---|
| Pages (from-to) | 7532-7537 |
| Number of pages | 6 |
| Journal | Journal of Materials Chemistry A |
| Volume | 6 |
| Issue number | 17 |
| DOIs | |
| State | Published - 2018 |
Funding
This work was supported by the U.S. Department of Energy (DOE), Office of Science, Office of Basic Energy Sciences, Chemical Sciences, Geosciences, and Biosciences Division. We thank Prof. Quan-Ming Wang and Prof. Lai-Sheng Wang for very helpful discussion. This research used resources of the National Energy Research Scientic Computing Center, a DOE Office of Science User Facility supported by the Office of Science of the U.S. Department of Energy under Contract DE-AC02-05CH11231.