Soto M, Boyer T A, Biradar S, Ge L, Vajtai R, Elías-Zúñiga A, Ajayan P M, Barrera E V
Department of Materials Science and NanoEngineering, Rice University, Houston, TX 77005, USA.
Nanotechnology. 2015 Apr 24;26(16):165201. doi: 10.1088/0957-4484/26/16/165201. Epub 2015 Mar 27.
Through this study, the results of density functional theory calculations within the local density approximation of the electronic structure of zigzag-zigzag double-walled carbon nanotubes (DWCNTs), with chiral indices (n, 0)@(m, 0) for n = 7-15, and m = 15-26, has been presented and the effects of interwall interaction and orbital hybridization on the electronic structure of these systems has been discussed. It was observed that the electronic band gap of the aforementioned DWCNTs depends on the interwall distance only for metallic-semiconductor configurations and on the intrinsic properties of the constituent tubes in all other combinations. It was also observed that the calculated band gap for most of the metallic-metallic DWCNTs was smaller than semiconductor-metallic, metallic-semiconductor, and semiconductor-semiconductor configurations. Metallic-semiconductor DWCNTs were found to be desirable for band gap tuning applications because of their dependence on interwall distance, opening up the possibility of using such systems in electronic device applications, such as transistors. Other applications include the use of DWCNTs in macroscopic carbon nanotube conducting wires, for which metallic-metallic and semiconducting-metallic zigzag-zigzag DWCNTs were found to be the most desirable configurations due to their small band gaps.
通过本研究，给出了在局域密度近似下对锯齿形-锯齿形双壁碳纳米管（DWCNT）电子结构进行密度泛函理论计算的结果，其中手性指数（n, 0）@(m, 0)，n = 7 - 15，m = 15 - 26，并讨论了壁间相互作用和轨道杂化对这些体系电子结构的影响。观察到上述DWCNT的电子带隙仅在金属-半导体构型中取决于壁间距离，而在所有其他组合中取决于组成管的本征性质。还观察到，大多数金属-金属DWCNT的计算带隙小于半导体-金属、金属-半导体和半导体-半导体构型。金属-半导体DWCNT因其对壁间距离的依赖性而被发现适用于带隙调谐应用，这为在诸如晶体管等电子器件应用中使用此类体系开辟了可能性。其他应用包括在宏观碳纳米管导线中使用DWCNT，对于此应用，金属-金属和半导体-金属锯齿形-锯齿形DWCNT因其小带隙而被发现是最理想的构型。
