Amphoteric doping of carbon nanotubes by encapsulation of organic molecules: Electronic properties and quantum conductance
Amphoteric doping of carbon nanotubes by encapsulation of organic molecules: Electronic properties and quantum conductance
复制标题
DOI：
10.1063/1.1931547
复制
发表时间：
2005-07-08
影响因子：
4.4
通讯作者：
Sumpter, BG
中科院分区：
文献类型：
--
作者：
Meunier, V;Sumpter, BG
为了研究和优化有机分子掺杂碳纳米管中的电子输运过程，我们进行了大规模的量子电子结构计算，并结合格林函数公式确定了量子电导。我们的方法是基于最初的方案，在该方案中，有限系统上的量子化学计算被重塑为无限的、非周期的(即，开放的)系统，从而模拟实际的工作装置。这些计算的结果清楚地表明，通过封装适当的有机分子可以很容易地操纵碳纳米管的电子结构。被包裹的有机分子诱导的电荷转移过程导致了碳纳米管的有效的n型和p型掺杂。尽管一个分子可以引起p和n的掺杂，但与原始的纳米管相比，它对纳米管的输运性质的影响很小。因此，这种类型的掺杂保留了原始管子作为弹道导体的固有特性。此外，有机分子和纳米管之间的有效电荷转移过程被证明显著降低了纳米管的pi电子对氧修饰的敏感性，同时在室温下保持稳定的掺杂(即，不脱掺杂)。(C)2005年美国物理研究所。
In order to investigate and optimize the electronic transport processes in carbon nanotubes doped with organic molecules, we have performed large-scale quantum electronic structure calculations coupled with a Green's function formulation for determining the quantum conductance. Our approach is based on an original scheme where quantum chemistry calculations on finite systems are recast to infinite, nonperiodic (i.e., open) systems, therefore mimicking actual working devices. Results from these calculations clearly suggest that the electronic structure of a carbon nanotube can be easily manipulated by encapsulating appropriate organic molecules. Charge transfer processes induced by encapsulated organic molecules lead to efficient n- and p-type doping of the carbon nanotube. Even though a molecule can induce p and n doping, it is shown to have a minor effect on the transport properties of the nanotube as compared to a pristine tube. This type of doping therefore preserves the intrinsic properties of the pristine tube as a ballistic conductor. In addition, the efficient process of charge transfer between the organic molecules and the nanotube is shown to substantially reduce the susceptibility of the pi electrons of the nanotube to modification by oxygen while maintaining stable doping (i.e., no dedoping) at room temperature. (c) 2005 American Institute of Physics.