Probing oxidation-controlled proton transfer at the graphene oxide-water interface with deep neural network force...

Area of Science:

• Materials Science
• Electrochemistry
• Surface Chemistry

Background:

• Proton transfer at interfaces is critical for electrochemical applications.
• Graphene oxide (GO) is a promising material for proton exchange membranes in fuel cells.
• The behavior of protons at the aqueous GO interface requires detailed investigation.

Purpose of the Study:

• To elucidate the mechanism of proton transfer at the aqueous graphene oxide interface.
• To compare the proton transfer behavior between oxidized and reduced GO sheets.
• To provide insights for designing efficient GO-based proton exchange membranes.

Main Methods:

• Deep Potential Molecular Dynamics (DPMD) simulations were employed.
• Simulations were performed on GO sheets with varying oxidation levels.
• Interfacial proton dynamics and adsorption/release were analyzed.

Main Results:

• Oxidized GO sheets were found to promote interfacial proton release.
• Reduced GO sheets were observed to adsorb protons.
• The oxidation level of GO significantly influences proton transfer dynamics.

Conclusions:

• The oxidation state of graphene oxide dictates its role in proton transfer at the aqueous interface.
• Oxidized GO facilitates proton transport, beneficial for fuel cell applications.
• Reduced GO's proton adsorption properties may require mitigation for optimal membrane performance.