Phys. Chem. Chem. Phys. (2016)
Anna Sofia Tascini, Jeff Armstrong, Eliodoro Chiavazzo, Matteo Fasano, Pietro Asinari and Fernando Bresme
We investigate the general dependence of the thermal transport across nanoparticle-fluid interfaces using molecular dynamics computations. We show that the thermal conductance depends strongly both on the wetting characteristics of the nanoparticle-fluid interface as well as on the nanoparticle size. Strong nanoparticle-fluid interactions, leading to full wetting states in the host fluid, result in high thermal conductances and efficient interfacial transport of heat. Weak interactions result in partial dry or dry states, and consistently low thermal conductances. The variation of the thermal conductance with particle size is found to depend on the fluid-nanoparticle interactions. Strong interactions coupled with large interfacial curvatures lead to optimum interfacial heat transport. This complex dependence can be modelled with an equation that includes the interfacial curvature as parameter. In this way we rationalise existing experimental and computer simulation results and show that the thermal transport across nanoscale interfaces is determined by the correlations of both interfacial curvature and nanoparticle-fluid interactions.