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A bottom-up route to enhance thermoelectric figures of merit in graphene nanoribbons.

ABSTRACT: We propose a hybrid nano-structuring scheme for tailoring thermal and thermoelectric transport properties of graphene nanoribbons. Geometrical structuring and isotope cluster engineering are the elements that constitute the proposed scheme. Using first-principles based force constants and Hamiltonians, we show that the thermal conductance of graphene nanoribbons can be reduced by 98.8% at room temperature and the thermoelectric figure of merit, ZT, can be as high as 3.25 at T = 800?K. The proposed scheme relies on a recently developed bottom-up fabrication method, which is proven to be feasible for synthesizing graphene nanoribbons with an atomic precision.

SUBMITTER: Sevincli H

PROVIDER: S-EPMC3565174 | biostudies-literature | 2013

REPOSITORIES: biostudies-literature

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A bottom-up route to enhance thermoelectric figures of merit in graphene nanoribbons.

Sevinçli Hâldun H Sevik Cem C Caın Tahir T Cuniberti Gianaurelio G

Scientific reports 20130206

We propose a hybrid nano-structuring scheme for tailoring thermal and thermoelectric transport properties of graphene nanoribbons. Geometrical structuring and isotope cluster engineering are the elements that constitute the proposed scheme. Using first-principles based force constants and Hamiltonians, we show that the thermal conductance of graphene nanoribbons can be reduced by 98.8% at room temperature and the thermoelectric figure of merit, ZT, can be as high as 3.25 at T = 800 K. The propos ...[more]

PMID: 23390578

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