Aromatic molecular junctions between graphene sheets: a molecular dynamics screening for enhanced thermal conductance

Area of Science:

• Materials Science
• Nanotechnology
• Computational Chemistry

Background:

• Developing efficient thermally-conductive nanocomposites is crucial for advanced heat management applications.
• Molecular junctions are key components for creating conductive pathways in nanomaterials.
• Understanding interfacial thermal transport is essential for optimizing nanocomposite performance.

Purpose of the Study:

• To design and evaluate molecular junctions for thermally-conductive nanocomposites using theoretical simulations.
• To correlate thermal conductance with molecular junction properties like length and stiffness.
• To propose a knowledge-driven approach for controlling interfacial thermal transport in nanomaterials.

Main Methods:

• Classical molecular dynamics simulations were employed to model molecular junctions.
• A variety of chemically viable molecular structures were investigated as thermal bridges between graphene nanosheets.
• Tensile deformation simulations and analysis of vibrational density of states were used to assess mechanical and vibrational properties.

Main Results:

• Thermal conductance was found to be dependent on the length and mechanical stiffness of the molecular junctions.
• The mechanical response of the molecular junctions was highly sensitive to subtle changes in chemical structure.
• Interfacial vibrational properties were analyzed to gain insights into thermal transport mechanisms.

Conclusions:

• A knowledge-driven design strategy for molecular junctions can effectively control interfacial thermal transport.
• Optimized molecular junctions can lead to more efficient heat management solutions in nanodevices.
• Potential applications include flexible heat spreaders, bulk heat exchangers, and heat storage devices.