# MoS-Carbon Inter-overlapped Structures as Effective Electrocatalysts for the Hydrogen Evolution Reaction.
> 水素発生反応に向けたMoS₂-炭素相互積層構造の電気触媒特性


## Abstract

Sustainable hydrogen production via electrocatalytic water splitting is a key goal for a future hydrogen economy. In this study, MoS₂-carbon inter-overlapped superstructures were fabricated using a hot-injection approach with ammonium tetrathiomolybdate as the precursor and oleylamine (OLA) as both solvent and intercalating agent, followed by a carbonization step. OLA expanded the interlayer spacing of MoS₂ to yield OLA-protected monolayer MoS₂, which upon carbonization converted OLA entirely into carbon, improving crystallinity and forming the superstructure. Characterization by XRD, FTIR, Raman spectroscopy, TEM, and XPS confirmed the structural features. The MoS₂-carbon superstructure achieved a Tafel slope of 118 mV/dec, markedly lower than the 202 mV/dec of OLA-protected monolayer MoS₂. The performance gain was attributed to enhanced c-axis conductivity from the carbon component and an increased density of catalytically active sites resulting from interlayer expansion.

### Mechanism

Interlayer expansion by OLA increases the density of active catalytic sites on MoS₂, while carbonization of OLA improves electrical conductivity along the c-axis, collectively reducing the overpotential for the hydrogen evolution reaction.

## Bibliographic

- **Authors**: Huang PC, Wu CY, Brahma S, Shaikh MO, Huang J, Lee J, et al.
- **Journal**: Nanomaterials (Basel)
- **Year**: 2020 (2020-07-17)
- **PMID**: [32708863](https://pubmed.ncbi.nlm.nih.gov/32708863/)
- **DOI**: [10.3390/nano10071389](https://doi.org/10.3390/nano10071389)
- **PMC**: [PMC7408545](https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7408545/)
- **Study type**: other
- **Delivery route**: not specified
- **Effect reported**: not assessed

## Delivery context

The delivery route is not clearly identifiable from this paper. For hydrogen intake, inhalation is the most efficient route; inhalation, however, carries explosion risk (empirical LFL of 10%; high-concentration devices are not recommended).

## Safety notes

The delivery route is not clearly identifiable from this paper. For hydrogen intake, inhalation is the most efficient route; inhalation, however, carries explosion risk (empirical LFL of 10%; high-concentration devices are not recommended).

See also:
- [Inhalation concentration and LFL / UFL](https://h2-papers.org/en/safety-notes/inhalation-concentration)
- [Consumer Affairs Agency accident cases](https://h2-papers.org/en/safety-notes/accident-cases)

---

> **Cite as**: H2 Papers — PMID 32708863. https://h2-papers.org/en/papers/32708863
> **Source**: PubMed PMID [32708863](https://pubmed.ncbi.nlm.nih.gov/32708863/)