Interfacial Stability and Confined Structures for Graphene/SiO₂ Composites in Water Media

Area of Science:

• Materials Science
• Nanotechnology
• Computational Chemistry

Background:

• Graphene/silica (SiO2) heterojunctions are utilized in nanoelectronic devices for sensing applications.
• Interfacial stability and structural characteristics of graphene/SiO2 composites in aqueous environments are not well understood.

Purpose of the Study:

• To investigate the adhesion and interfacial stability of graphene/SiO2 composites in water using molecular simulations.
• To explore the influence of SiO2 surface types and hydrophilicity on graphene adhesion.
• To elucidate the microscopic mechanisms governing interfacial behavior in aqueous media.

Main Methods:

• Molecular dynamics simulations were employed to model graphene/SiO2 interfaces.
• Thermodynamic free energy calculations were performed to quantify interfacial interaction and adhesion strength.
• Analysis of morphological transformations and hydration structures at the interface.

Main Results:

• SiO2 substrates exhibit varying affinities for graphene, influencing adhesion strength.
• Increased SiO2 hydrophilicity significantly reduces graphene adhesion in aqueous environments due to hydration forces.
• Morphological changes and hydration layer structures critically modulate interface stability.

Conclusions:

• Water plays a crucial role in modulating the adhesion and stability of graphene/SiO2 interfaces, unlike in dry conditions.
• Understanding these aqueous interfacial dynamics is vital for designing robust graphene-based sensors and nanoelectronic devices.