File Download

There are no files associated with this item.

  • Find it @ UNIST can give you direct access to the published full text of this article. (UNISTARs only)
Related Researcher

이현욱

Lee, Hyun-Wook
Read More

Views & Downloads

Detailed Information

Cited time in webofscience Cited time in scopus
Metadata Downloads

Ordered Mesoporous Metastable α-MoC 1− x with Enhanced Water Dissociation Capability for Boosting Alkaline Hydrogen Evolution Activity

Author(s)
Baek, Du SanJung, Gwan YeongSeo, BoraKim, Jin ChulLee, Hyun-WookShin, Tae JooJeong, Hu YoungKwak, Sang KyuJoo, Sang Hoon
Issued Date
2019-07
DOI
10.1002/adfm.201901217
URI
https://scholarworks.unist.ac.kr/handle/201301/27019
Fulltext
https://onlinelibrary.wiley.com/doi/full/10.1002/adfm.201901217
Citation
ADVANCED FUNCTIONAL MATERIALS, v.29, no.28, pp.1901217
Abstract
The sluggish reaction kinetics of the alkaline hydrogen evolution reaction (HER) remains an important challenge for water–alkali electrolyzers, which originates predominantly from the additional water dissociation step required for the alkaline HER. In this work, it is demonstrated theoretically and experimentally that metastable, face-centered-cubic α-MoC 1− x phase shows superior water dissociation capability and alkaline HER activity than stable, hexagonal-close-packed Mo 2 C phase. Next, high surface area ordered mesoporous α-MoC 1− x (MMC) is designed via a nanocasting method. In MMC structure, the α-MoC 1− x phase facilitates the water dissociation reaction, while the mesoporous structure with high surface area enables a high dispersion of metal NPs and efficient mass transport. As a result, Pt nanoparticles (NPs) supported on MMC (Pt/MMC) show substantially enhanced alkaline HER activity in terms of overpotentials, Tafel slopes, mass and specific activities, and exchange current densities, compared to commercial Pt/C and Pt NPs supported on particulate α-MoC 1− x or β-Mo 2 C. Notably, Pt/MMC shows very low Tafel slope of 30 mV dec –1 , which is the lowest value among the reported Pt-based alkaline HER catalysts, suggesting the critical role of MMC in enhancing the HER kinetics. The promotional effect of MMC support in the alkaline HER is further demonstrated with an Ir/MMC catalyst.
Publisher
Wiley-VCH Verlag
ISSN
1616-301X
Keyword (Author)
alkaline electrolyzershydrogen evolution reactionmesoporous materialsmolybdenum carbidewater dissociation
Keyword
CarbidesCatalystsDissociationElectrolytic cellsHydrogenMolybdenum compoundsPlatinumReaction kineticsElectrolyzersExchange current densitiesFace-centered cubicHexagonal close packedHydrogen evolution reactionsMesoporous structuresMolybdenum carbideWater dissociationMesoporous materials

qrcode

Items in Repository are protected by copyright, with all rights reserved, unless otherwise indicated.