Hydrogen evolution enhancement of ultra-low loading, size-selected molybdenum sulfide nanoclusters by sulfur enrichment

Daniel Escalera-López, Yubiao Niu, Sung Jin Park, Mark Isaacs, Karen Wilson, Richard E. Palmer, Neil V. Rees

Research output: Contribution to journalArticlepeer-review

27 Citations (Scopus)
141 Downloads (Pure)

Abstract

Size-selected molybdenum sulfide (MoSx) nanoclusters obtained by magnetron sputtering and gas condensation on glassy carbon substrates are typically sulfur-deficient (x = 1.6 ± 0.1), which limits their crystallinity and electrocatalytic properties. Here we demonstrate that a sulfur-enriching method, comprising sulfur evaporation and cluster annealing under vacuum conditions, significantly enhances their activity towards the hydrogen evolution reaction (HER). The S-richness (x = 4.9 ± 0.1) and extended crystalline order obtained in the sulfur-treated MoSx nanoclusters lead to consistent 200 mV shifts to lower HER onset potentials, along with two-fold and more-than 30-fold increases in turnover frequency and exchange current density values respectively. The high mass activities (∼111 mA mg−1 @ 400 mV) obtained at ultra-low loadings (∼100 ng cm-2, 5% surface coverage) are comparable to the best reported MoS2 catalysts in the literature.

Original languageEnglish
Pages (from-to)84-91
Number of pages8
JournalApplied Catalysis B: Environmental
Volume235
Early online date27 Apr 2018
DOIs
Publication statusPublished - 5 Nov 2018

Keywords

  • Hydrogen evolution
  • Magnetron sputtering deposition
  • Molybdenum sulfide
  • Nanoclusters
  • Sulfur-rich

ASJC Scopus subject areas

  • Catalysis
  • Environmental Science(all)
  • Process Chemistry and Technology

Fingerprint

Dive into the research topics of 'Hydrogen evolution enhancement of ultra-low loading, size-selected molybdenum sulfide nanoclusters by sulfur enrichment'. Together they form a unique fingerprint.

Cite this