Low lattice thermal conductivity of stanene

TL;DR

This study calculates the lattice thermal conductivity of stanene using first-principles and Boltzmann transport, revealing its low thermal conductivity and implications for thermoelectric applications.

Contribution

It provides the first detailed analysis of phonon transport and size dependence in stanene, highlighting its potential for thermoelectric devices.

Findings

Stanene has a low thermal conductivity of 11.6 W/mK.

High-group-velocity LA phonons dominate thermal transport.

Size effects influence thermal conductivity for nanostructure design.

Abstract

A fundamental understanding of phonon transport in stanene is crucial to predict the thermal performance in potential stanene-based devices. By combining first-principle calculation and phonon Boltzmann transport equation, we obtain the lattice thermal conductivity of stanene. A much lower thermal conductivity (11.6 W/mK) is observed in stanene, which indicates higher thermoelectric efficiency over other 2D materials. The contributions of acoustic and optical phonons to the lattice thermal conductivity are evaluated. Detailed analysis of phase space for three-phonon processes shows that phonon scattering channels LA+LA/TA/ZA$\leftrightarrow$TA/ZA are restricted, leading to the dominant contributions of high-group-velocity LA phonons to the thermal conductivity. The size dependence of thermal conductivity is investigated as well for the purpose of the design of thermoelectric nanostructures.