Dual-mode solid-state thermal rectification

Ramesh Shrestha,Sheng Shen,Teng Zhang,Phil Smith,Kedar Hippalgaonkar,Xiao Luo,Wei Gong,Renkun Chen,Sunmi Shin,Tengfei Luo,Michael Bockstaller,Yuxuan Luan

doi:10.1038/s41467-020-18212-2

Abstract

Thermal rectification is an exotic thermal transport phenomenon which allows heat to transfer in one direction but block the other. We demonstrate an unusual dual-mode solid-state thermal rectification effect using a heterogeneous “irradiated-pristine” polyethylene nanofiber junction as a nanoscale thermal diode, in which heat flow can be rectified in both directions by changing the working temperature. For the nanofiber samples measured here, we observe a maximum thermal rectification factor as large as ~50%, which only requires a small temperature bias of <10 K. The tunable nanoscale thermal diodes with large rectification and narrow temperature bias open up new possibilities for developing advanced thermal management, energy conversion and, potentially thermophononic technologies.

Highlights

Thermal rectification is an exotic thermal transport phenomenon which allows heat to transfer in one direction but block the other
As suggested by molecular dynamics study[28], strain can help restore the highly ordered phase at low temperatures, and the thermal switching ratio varies with the strain of the PE nanofiber
By fabricating the irradiated-pristine junction as a nanoscale thermal diode, we demonstrate dual-mode solid-state thermal rectification in which heat flow is rectified from either the forward or the reverse direction depending on the working temperature

Summary

Introduction

Thermal rectification is an exotic thermal transport phenomenon which allows heat to transfer in one direction but block the other. The LI-P nanofiber junction shows a unique dual-mode thermal rectification effect, which can switch modes to rectify heat flow in both directions by changing the working temperature.

Results

Conclusion