Disclosing the contribution of vacancy defects to thermal transport at a liquid-Al/graphene adhesion interface

Abstract

The adhesion properties of liquid–solid interfaces are of fundamental importance in the performance and design of nanodevices. Modulating interfacial thermal transport has the potential to enhance interfacial heat dissipation in nanodevices. Herein, the adhesive characteristics of the liquid–solid interface formed by liquid-Al/graphene are reported using molecular dynamics, and the intrinsic mechanism of interfacial adhesion evolution and energy-heat transport is revealed. Specifically, an increase in temperature significantly reduces the adhesion and thermal transport capacity. Concurrently, the expansion of vacancy defects strengthens the interfacial adhesion property. This is due to the fact that the enlarged vacancy defects enhance the local contact and interfacial thermal conductance (ITC) between the atoms, thereby optimizing interfacial energy transport. The augmented ITC facilitates interfacial energy-heat exchange and phonon participation rate (PPR), and thus increases interfacial phonon modes and further reinforces the adhesion strength. This paper elucidates the evolution of interfacial adhesion characteristics of liquid-Al/graphene, providing substantial guidance for a more comprehensive understanding of energy transport at the liquid–solid interface.