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Updated: Aug 27, 2025
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Probing the Structure and Dynamics of Interfacial Water with Scanning Tunneling Microscopy and Spectroscopy
Published on: May 27, 2018
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Wien effect in interfacial water dissociation through proton-permeable graphene electrodes
J Cai1,2,3, E Griffin1,2, V H Guarochico-Moreira1,2,4
1National Graphene Institute, The University of Manchester, Manchester, M13 9PL, UK.
Nature Communications
|October 1, 2022
Summary
Researchers observed the Wien effect in water dissociation using graphene electrodes, achieving electric fields over 108 V m-1. This breakthrough accelerates interfacial water splitting and offers new insights into proton transport phenomena.
Area of Science:
- Physical Chemistry
- Materials Science
- Electrochemistry
Background:
- The Wien effect, or field-induced molecular dissociation, was previously observed for weak electrolytes using high-voltage electrolysis.
- Achieving the Wien effect for water dissociation (H2O ⇌ H+ + OH-) has been a long-standing challenge in physical chemistry.
Purpose of the Study:
- To investigate the dissociation of interfacial water under strong electric fields.
- To observe and quantify the Wien effect in water using novel electrode materials.
- To explore the utility of graphene electrodes for studying interfacial proton transport.
Main Methods:
- Utilizing proton-permeable graphene electrodes to create strong electric fields (> 108 V m-1) at the interface.
- Measuring proton currents exclusively from interfacial water dissociation.
- Monitoring the electric field strength via carrier density changes induced in graphene.
Main Results:
- Observed strong acceleration of water dissociation under electric fields exceeding 108 V m-1.
- Proton currents showed an exponential increase, consistent with Onsager's dissociation theory.
- Demonstrated graphene electrodes' capability to isolate and measure interfacial water dissociation currents.
Conclusions:
- Graphene electrodes facilitate the observation of the Wien effect in water dissociation.
- The study provides quantitative agreement with theoretical models of field-induced dissociation.
- Graphene electrodes are promising tools for investigating interfacial phenomena, particularly proton transport.
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