Electronic and magnetic properties of nitrogen-doped finite-size and open-ended zigzag carbon nanotubes
Electronic and magnetic properties of nitrogen-doped finite-size and open-ended zigzag carbon nanotubes
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氮掺杂有限尺寸开口锯齿形碳纳米管的电子和磁性能
DOI：
10.1016/j.commatsci.2011.01.039
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发表时间：
2011-04-01
影响因子：
3.3
通讯作者：
Cao, Zexing
中科院分区：
文献类型：
--
作者：
Tang, Shaobin;Cao, Zexing
利用密度泛函计算研究了N掺杂对有限尺寸、开口锯齿形碳纳米管（CNT）电子和磁性的影响。与其他位点相比，边缘位点处的碳原子更容易被N原子能量地取代。单个N原子的取代可以降低掺杂位置附近边缘碳原子的磁矩，从而抑制自旋极化。这种自旋抑制是独立的管直径，它可以归因于在掺杂的边缘本地化的π/π * 状态的扰动。在低N掺杂浓度下，有限长锯齿形碳纳米管可以保持反铁磁（AFM）基态，但在高杂质浓度下可以发生从AFM到反铁磁态的转换。更有趣的是，从半半导体到半导体状态的可调的电子性质可以实现在这些N掺杂的有限尺寸和开放式的碳纳米管，如果受到一个沿管轴沿着的外部电场。(C)2011 Elsevier B. V.保留所有权利。
Density functional calculations have been used to investigate the effect of the N doping on the electronic and magnetic properties of finite-size and open-ended zigzag carbon nanotubes (CNT). The carbon atoms at the edge site are more easily replaced by N atoms energetically, compared to other sites. The single N atom substitution can reduce the magnetic moment of edge carbon atoms near the doping site and result in the suppression of spin polarization. Such spin suppression is independent of tube diameter and it can be ascribed into perturbation of the pi/pi* state localized at the doped edge. At low N-doping concentrations, the finite-length zigzag CNTs can maintain an antiferromagnetic (AFM) ground state, but the conversion from AFM to a nonmagnetic state can occur at high impurity concentrations. More interestingly, the tunable electronic properties from the half-semiconducting to semiconducting state can be realized in these N-doped finite-size and open-ended CNTs if subjected to a variably external electric field along the tube axis. (C) 2011 Elsevier B.V. All rights reserved.