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Updated: May 17, 2025
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Fabrication of Three-Dimensional Graphene-Based Polyhedrons via Origami-Like Self-Folding
Published on: September 23, 2018
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Protons Accumulate at the Graphene-Water Interface
Xavier R Advincula1,2,3, Kara D Fong1,3, Angelos Michaelides1,3
1Yusuf Hamied Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge CB2 1EW, U.K.
ACS Nano
|April 28, 2025
Summary
Protons accumulate at the graphene-water interface, with hydronium ions in the first water layer. Hydroxide ions show a dual distribution, impacting surface properties and reactivity.
Area of Science:
- Physical Chemistry
- Surface Science
- Computational Materials Science
Background:
- Water autoionization creates hydroxide and hydronium ions, influencing interfacial properties.
- Proton affinity to the air-water interface is known, but behavior at graphene-water interfaces is unclear.
Purpose of the Study:
- To investigate the behavior of hydroxide and hydronium ions at the graphene-water interface.
- To understand the impact of ion distribution on interfacial properties and reactivity.
Main Methods:
- Utilizing machine learning-based simulations with first-principles accuracy.
- Analyzing the electronic structure to understand charge rearrangement and polarization effects.
Main Results:
- Protons (hydronium ions) accumulate at the graphene-water interface, primarily in the first water layer.
- Hydroxide ions exhibit a bimodal distribution, appearing both near and further from the surface.
- Local polarization effects and counterintuitive charge rearrangement were observed at the interface.
Conclusions:
- Proton accumulation at the graphene-water interface challenges existing experimental interpretations.
- Findings have significant implications for ion conductivity, interfacial reactivity, and proton-mediated processes.
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