Thermal conductivity prediction of copper hollow nanowire

Abstract

Because its superficial area is larger than that of a nanowire, hollow nanowires have drawn more and more attention in solar cells, lithium ion batteries, and other potential applications. The thermal property of a hollow nanowire is useful, but there is little study on the matter. This paper marks the first careful study of the metallic hollow nanowire's thermal conductivity. The electron mean free path was simulated, and a fitting model for easy calculation was established based on that simulation. With an electron mean free path already obtained, the electronic thermal conductivity can be easily determined. At the same time, a model based on the ballistic-diffusive effective medium model was established to calculate the lattice thermal conductivity of a hollow nanowire. In the study of copper hollow nanowires, it turns out that: model results of the lattice thermal conductivity agree with results obtained by molecular dynamics. The size effect of the electronic or lattice thermal conductivity of a hollow nanowire is characterized well by the equivalent diameter. With a similar diameter, the electronic or lattice thermal conductivity of a hollow nanowire approximately equals with that of a nanowire. From the point of thermal conductivity, the hollow nanowire will be a good substitute for the nanowire.