Size and edge roughness dependence of thermal conductivity for vacancy-defective graphene ribbons

作者:Xie, Guofeng*; Shen, Yulu
来源:Physical Chemistry Chemical Physics, 2015, 17(14): 8822-8827.
DOI:10.1039/c5cp00335k

摘要

By incorporating the phonon-phonon scattering, phonon-boundary scattering and phonon-vacancy scattering into the linearized Boltzmann transport equation, we theoretically investigate the effects of size and edge roughness on thermal conductivity of single vacancy-defective graphene ribbons. Due to the severe suppression of high-frequency phonons by phonon-vacancy scattering which includes the impacts of missing mass and linkages, as well as the variation of the force constant of bonds associated with vacancies, the low-frequency ballistic phonons have a higher contribution to the thermal conductivity, which results in the stronger length, weaker width and weaker edge roughness dependence on thermal conductivity of vacancy-defective graphene ribbons than that of pristine ones. Our findings are helpful to understand and manipulate thermal conductivity of graphene by phononic engineering.