Engineering thermal rectification in MoS₂nanoribbons: a non-equilibrium molecular dynamics study

Abstract

Phononics in two-dimensional (2D) materials is an emergent field with a high potential impact from the basic as well as applied research points of view. Hereby it is crucial to provide strategies to control heat flow via atomic-scale engineering of the materials. In this study, thermal diodes made of single layer MoS 2 nanoribbons are investigated using non-equilibrium classical molecular dynamics. Specifically, we focus on the influence of shape asymmetries of the nanoribbons on the thermal current, and obtain thermal rectification ratios up to 30% for T-shaped nanoribbons. This behavior is then rationalized through a detailed analysis of the vibrational spectrum of the ribbons. In particular, it turns out that thermal rectification is mostly related to (i) the transversal finite size of the ribbon and (ii) to the different localization behavior of high-frequency modes for forward and backward heat flow directions. We expect our results to shed light on the potential of 2D materials for engineering highly efficient nanoscale thermal devices.

Significantly High Thermal Rectification in an Asymmetric Polymer Molecule Driven by Diffusive versus Ballistic Transport

“…The underlying mechanism for nanoscale thermal rectification is under debate and it should, perhaps, not be considered to be one-fold. Sufficient conditions for thermal rectification in nanostructures were found to vary over a wide range including vibrational spectrum mismatch, − asymmetric coupling with thermal contacts, , phonon localization, − phonon lateral confinement, standing wave formation, and presence of solitons …”

Fluidic and Mechanical Thermal Control Devices

“…Thermal management is a common issue in several applications including cryogenics, [ 10–12 ] energy conversion, [ 13–15 ] caloric refrigeration, [ 16–18 ] microfluidics, [ 19–21 ] biology, chemistry, and pharmacy, [ 22–24 ] buildings, [ 25–28 ] outer space, [ 11,29,30 ] and sensor technologies. [ 31,32 ] Therefore, TCDs for these application areas are being studied theoretically and experimentally.…”

Thermal rectification in silicon by a graded distribution of defects

“…This basically requires that such a sharp interface is not present in the rectifying device. In this regard, low-dimensional systems (either model or realistic) prompt several possible rectifying configurations, such as non-uniform mass loading, suited distributions of defects, and tailored shaping, [11][12][13][14][15][16][17][18][19][20]33 where the above combination is actually realized. In this work, we further exploit this concept in bulk-like systems.…”