No Cover Image

Journal article 141 views 13 downloads

MoS 2 and WS 2 nanocone arrays: Impact of surface topography on the hydrogen evolution electrocatalytic activity and mass transport / Daniel Escalera-López; Ross Griffin; Mark Isaacs; Karen Wilson; Richard E. Palmer; Neil V. Rees

Applied Materials Today, Volume: 11, Pages: 70 - 81

Swansea University Author: Palmer, Richard

  • escaler-lopez2018.pdf

    PDF | Version of Record

    Released under the terms of a Creative Commons Attribution 4.0 International license (CC-BY).

    Download (2.96MB)

Abstract

We report the fabrication and electrochemical study of edge-abundant transition metal dichalcogenide (TMD) nanocone arrays. Time-dependent etching by sequential use of isotropic O2 and anisotropic SF6/C4F8 plasmas on nanosphere monolayer-modified TMD crystals results in very high coverage nanocone a...

Full description

Published in: Applied Materials Today
ISSN: 2352-9407
Published: 2018
Online Access: Check full text

URI: https://cronfa.swan.ac.uk/Record/cronfa38882
Tags: Add Tag
No Tags, Be the first to tag this record!
Abstract: We report the fabrication and electrochemical study of edge-abundant transition metal dichalcogenide (TMD) nanocone arrays. Time-dependent etching by sequential use of isotropic O2 and anisotropic SF6/C4F8 plasmas on nanosphere monolayer-modified TMD crystals results in very high coverage nanocone array structures with tunable aspect ratios and interspacings. Electrochemical characterization of these arrays via the hydrogen evolution reaction (HER), using a low proton concentration electrolyte (2 mM HClO4, 0.1 M NaClO4) to reveal morphology-dependent mass transport features at the proton diffusion-controlled region, show significant changes in electrocatalytic behaviour at both WS2 and MoS2: notably onset potential shifts of 100 and 200 mV, and Tafel slope decreases of 50 and 120 mV dec−1 respectively. These improvements vary according to the geometry of the arrays and the availability of catalytic edge sites, and thus the observed electrochemical behaviour can be rationalized via kinetic and mass transport effects.
Keywords: Transition metal dichalcogenides; Hydrogen evolution; Nanoelectrode array; Plasma etching
College: College of Engineering
Start Page: 70
End Page: 81