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Anomalous thermal conductivity enhancement in low dimensional resonant nanostructures due to imperfections

journal contribution
posted on 08.10.2021, 13:53 by Hongying Wang, Yajuan Cheng, Zheyong Fan, Yangyu Guo, Zhongwei Zhang, Marc Bescond, Massahiro Nomura, Tapio Ala-NissilaTapio Ala-Nissila, Sebastian Volz, Shiyun Xiong

Nanophononic metamaterials have broad applications in fields such as heat management, thermoelectric energy conversion, and nanoelectronics. Phonon resonance in pillared low-dimensional structures has been suggested to be a feasible approach to reduce thermal conductivity (TC). In this work, we study the effects of imperfections in pillared nanostructures based on graphene nanoribbons (GNR), using classical molecular dynamics simulations and harmonic lattice dynamics. The TC of perfect pillared GNR is only about 13% of that of pristine GNR due to the strong phonon resonant hybridization in pillared GNR. However, introducing imperfections such as vacancy defects and mass mismatch between the pillars and the base material, and alloy disorder in the pillars, can weaken the resonant hybridization and abnormally increase the TC. We show that both vacancy defects and mass mismatch can reduce the penetration of the resonant modes from the pillars into the base material, while the alloy disorder in the pillars can scatter the phonons inside them, which turns regular resonance into a random one with weaker hybridization. Our work provides useful insight into the phonon resonance mechanisms in experimentally relevant low dimensional nanostructures containing various imperfections.

Funding

National Natural Science Foundation of China (NSFC) (No. 11804242), Collaborative Innovation Center of Suzhou Nano Science & Technology (NanoCIC), the Priority Academic Program Development of Jiangsu Higher Education Institutions (PAPD), the 111 Project, and Joint International Research Laboratory of Carbon-Based Functional Materials and Devices

NSFC (No. 11974059)

Academy of Finland QTF Centre of Excellence program (Project 312298)

History

School

  • Science

Department

  • Mathematical Sciences

Published in

Nanoscale

Volume

13

Issue

22

Pages

10010 - 10015

Publisher

Royal Society of Chemistry (RSC)

Version

AM (Accepted Manuscript)

Rights holder

© Royal Society of Chemistry

Publisher statement

This paper was accepted for publication in the journal Nanoscale and the definitive published version is available at https://doi.org/10.1039/d1nr01679b.

Acceptance date

06/05/2021

Publication date

2021-05-14

Copyright date

2021

ISSN

2040-3364

eISSN

2040-3372

Language

en

Depositor

Prof Tapio Ala-Nissila. Deposit date: 7 October 2021