碳纳米管内Ni纳米线的螺旋度与热稳定性研究

摘要

本文采用分子动力学模拟方法研究了扶手型碳纳米管包裹Ni纳米线的复合结构，主要讨论内部Ni纳米线的螺旋度和热稳定性．结果表明，Ni纳米线为多壳层螺旋结构，各壳层是由多条Ni原子链螺旋而成，不同层的螺旋度不同，内层的螺旋度明显大于外层．当每层的Ni原子链条数为3的整数倍时，其螺旋度最大．Ni纳米线的螺旋度与碳纳米管的管径相关，各层螺旋度的大小随管径的增加有明显的周期性变化．碳纳米管对Ni纳米线有很好的保护作用，即使是高温对Ni纳米线的结构及螺旋度也影响很小．%Molecular dynamics calculations are performed to study the structures of armchair carbon nanotubes （CNTs） encapsulating Ni nanowires and their helicities and thermal stabilities are discussed. It is found that Ni nanowires are of multiple helical tubular structure and each layer is composed of several Ni atom chains. Different layers of Ni nanowires have different helicities and the helicities of Ni nanowires in the inner layer are greater than those of the outer one. What is more, the helicity will be greatest when the number of the Ni atom chains is an integer multiple of three. As the increases of the diameters of the CNTs, the helicities of Ni nanowires change periodically. The structure and helicity only have tiny variations even at high temperature as the CNTs can protect the Ni nanowire.