On the thermoelectric transport properties of graphyne by the first-principles method
热电材料
态密度
电阻率和电导率
电子结构
作者
Xiaoming Wang,Dong-Chuan Mo,Shu-Shen Lu
出处
期刊:Journal of Chemical Physics [American Institute of Physics] 日期:2013-05-22卷期号:138 (20): 204704-204704被引量:54
标识
DOI:10.1063/1.4806069
摘要
Graphyne, another two-dimensional carbon allotrope, has received increased attentions in recent years. By using the first-principles density functional calculations combined with the non-equilibrium Green's function formalism, we investigated the electronic, thermal, and thermoelectric transport properties of graphyne systematically and comparatively. It is found that the phonon thermal conductance of graphyne is greatly reduced compared to that of graphene in most temperature regions while larger than that of graphene at low temperatures, which is attributed to the different bond strengths and phonon spectra of graphyne and graphene. Due to the semiconductor property of graphyne, the thermoelectric power (TEP) is found to be one magnitude larger than that of graphene. Besides, distinct peak value regions of TEP in the contour of chemical potential and temperature are displayed for graphyne and graphene. Finally, the thermoelectric figure of merit (ZT) of graphyne is found to be much larger than that of graphene as a result of large TEP and greatly reduced thermal conductance in graphyne, which indicates preferred thermoelectric applications for graphyne.