Volcano‐Type Behavior in Spatially Resolved Electron Transfer and Hydrogen Evolution Reaction Mapping over 2D Electrocatalysts
Journal
Small Methods
Journal Volume
9
Journal Issue
9
Start Page
e01169
ISSN
2366-9608
2366-9608
Date Issued
2025-08-06
Author(s)
Kholimatussadiah, Septia
Qorbani, Mohammad
Liu, Yu‐Ling
Raman, Radha
Lai, Ying‐Ren
Huang, Chih‐Yang
Chen, Kuei‐Hsien
Abstract
In situ mapping of interfacial electron transfer dynamics to reveal electrocatalytic activity with high spatial resolution is crucial for developing efficient electrochemical devices. While emerging 2D materials for catalysis have attracted substantial attention, there is still a notable lack of studies examining their electrochemical properties at the nanoscale, particularly in a layer-by-layer context. Here, both outer-sphere and inner-sphere electron transfer at a 2D semiconducting WSe2 electrode–electrolyte interface are spatially resolved and quantified in high resolution. The investigations reveal that WSe2 exhibits a volcano-type behavior in its electrochemical activity, with a peak performance observed at a specific thickness of four layers. This phenomenon is attributed to the interplay between the layer-specific electronic density of states and the tunneling of charge carriers across the interlayer regions. This observation is further exemplified by micro-electrochemical hydrogen evolution reaction measurements.
Subjects
electrochemistry
electron transfer
hydrogen evolution reaction
scanning electrochemical microscopy
WSe2
Publisher
Wiley
Type
journal article