Publication detail

Allotrope-dependent activity-stability relationships of molybdenum sulfide hydrogen evolution electrocatalysts

Escalera-López, D. Iffelsberger, C. Zlatar, M. Novcic, K. Maselj, N. Van Pham, C. Jovanovic, P. Hodnik, N. Thiele, S. Pumera, M. Cherevko, S.

Original Title

Allotrope-dependent activity-stability relationships of molybdenum sulfide hydrogen evolution electrocatalysts

Type

journal article in Web of Science

Language

English

Original Abstract

Molybdenum disulfide (MoS2) is widely regarded as a competitive hydrogen evolution reaction (HER) catalyst to replace platinum in proton exchange membrane water electrolysers (PEMWEs). Despite the extensive knowledge of its HER activity, stability insights under HER operation are scarce. This is paramount to ensure long-term operation of Pt-free PEMWEs, and gain full understanding on the electrocatalytically-induced processes responsible for HER active site generation. The latter are highly dependent on the MoS2 allotropic phase, and still under debate. We rigorously assess these by simultaneously monitoring Mo and S dissolution products using a dedicated scanning flow cell coupled with downstream analytics (ICP-MS), besides an electrochemical mass spectrometry setup for volatile species analysis. We observe that MoS2 stability is allotrope-dependent: lamellar-like MoS2 is highly unstable under open circuit conditions, whereas cluster-like amorphous MoS3-x instability is induced by a severe S loss during the HER and undercoordinated Mo site generation. Guidelines to operate non-noble PEMWEs are therefore provided based on the stability number metrics, and an HER mechanism which accounts for Mo and S dissolution pathways is proposed. The stability of non-noble catalysts is key for their use in proton exchange membrane water electrolysers. Here, authors study activity-stability relationships of MoSx allotropes for H2 production, reporting allotrope-dependent stabilities and dissolution pathways, and propose operation guidelines.

Keywords

CATALYTIC-ACTIVITY; EVOLVING CATALYST; PHASE-TRANSITION; SULFUR VACANCIES; NATURAL CRYSTALS; EDGE SITES; MOS2; IDENTIFICATION; MONOLAYER; SPECTROSCOPY

Authors

Escalera-López, D.; Iffelsberger, C.; Zlatar, M.; Novcic, K.; Maselj, N.; Van Pham, C.; Jovanovic, P.; Hodnik, N.; Thiele, S.; Pumera, M.; Cherevko, S.

Released

29. 4. 2024

Publisher

NATURE PORTFOLIO

Location

BERLIN

ISBN

2041-1723

Periodical

NATURE COMMUNICATIONS

Year of study

15

Number

1

State

United Kingdom of Great Britain and Northern Ireland

Pages count

13

URL

https://www.nature.com/articles/s41467-024-47524-w

BibTex

@article{BUT189968,
  author="Escalera-López, D. and Iffelsberger, C. and Zlatar, M. and Novcic, K. and Maselj, N. and Van Pham, C. and Jovanovic, P. and Hodnik, N. and Thiele, S. and Pumera, M. and Cherevko, S.",
  title="Allotrope-dependent activity-stability relationships of molybdenum sulfide hydrogen evolution electrocatalysts",
  journal="NATURE COMMUNICATIONS",
  year="2024",
  volume="15",
  number="1",
  pages="13",
  doi="10.1038/s41467-024-47524-w",
  issn="2041-1723",
  url="https://www.nature.com/articles/s41467-024-47524-w"
}