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arXiv · 1308.4474

First-principles study of the thermoelectric properties of strained graphene nanoribbons

Pei Shan Emmeline Yeo·Michael B. Sullivan·Kian Ping Loh·Chee Kwan Gan
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Abstract

We study the transport properties, in particular, the thermoelectric figure of merit ZT of armchair graphene nanoribbons, AGNR-N (for N=4-12, with widths ranging from 3.7 to 13.6~\AA) through strain engineering, where N is the number of carbon dimer lines across the AGNR width. We find that the tensile strain applied to AGNR-$N$ changes the transport properties by modifying the electronic structures and phonon dispersion relations. The tensile strain increases the ZT value of the AGNR-$N$ families with N=3p and N=3p+2, where $p$ is an integer. Our analysis based on accurate density-functional theory calculations suggests a possible route to increase the ZT values of AGNR-$N$ for potential thermoelectric applications.

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Pei Shan Emmeline Yeo, Michael B. Sullivan, Kian Ping Loh, Chee Kwan Gan. 2013-08-21. First-principles study of the thermoelectric properties of strained graphene nanoribbons. https://doi.org/10.1039/c3ta12211e

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