Nanoscale study on enhanced interfacial heat transfer in confined space with spontaneously formed diol molecular bridge

Nanoconfinement technology is widely used in thermal energy storage application for alleviating energy shortage crisis. In this work, the nanoconfinement effect of diol molecules on the thermal transport characteristic between two hydrophilic silica interfaces was studied based on the molecular dynamics simulation. The results show that nanoconfinement can induce spontaneously formed diol molecular bridges connecting two silica surfaces, which can significantly improve the overall interfacial thermal conductance. It is further found that the spontaneous formation of molecular bridges can be regulated by the spacing between two solid surfaces and also the operating temperature. The overall interfacial thermal conductance with molecular bridges is at least twice that without molecular bridges when the spacings are close. The findings in this work prove one potential strategy to enhance the interfacial heat transfer of organics with a low thermal conductivity, especially for amphiphilic substances, in the field of thermal energy storage.