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第 34 卷 第 6 期, pp.235-257  (2014) [ 23页 ]

纳米材料的螺旋生长

陈伟
材料液固结构演变与加工教育部重点实验室,材料科学与工程学院,山东大学,250061

李辉
材料液固结构演变与加工教育部重点实验室,材料科学与工程学院,山东大学,250061

李云芳
材料液固结构演变与加工教育部重点实验室,材料科学与工程学院,山东大学,250061

2015/04/09 发布

因其独特的结构特点,纳米材料的螺旋生长一直备受关注。在本综述中,主要采用分子动力学方法来模拟指定材料间的相互作用。模拟结果证明,石墨烯纳米带能够自发螺旋嵌入碳纳米管,亦能螺旋缠绕在碳纳米管外壁,而这一结果已被实验证实。同时,封闭的石墨烯纳米环可填充到碳纳米管空腔中形成类似DNA 的双螺旋结构,亦能螺旋塌陷在碳纳米管外壁形成大螺距双层螺旋结构。模拟发现,石墨烯纳米带与石墨烯纳米环均可螺旋缠绕在金属纳米线外壁形成碳¡金属壳核结构,这一机理可用于制备壳核复合结构。另外,我们论述了硅纳米粒子在碳纳米锥与碳纳米管表面的螺旋形核机制。通过相互作用机制和热力学模型的建立来进一步研究纳米材料的螺旋生长。据推断,螺旋结构具有最低的能量且具有最高的空间利用率。同时,实验证明,极性面以及螺旋位错
的存在也可驱动晶体结晶过程中的螺旋生长。到目前,尽管涉及纳米材料螺旋生长的研究非常广泛,但还需要更详实的后续研究来解释螺旋生长的作用机制。
Spiral growth of nanomaterials has gained ever-increasing research interest due to its special arrangement. In this review, molecular dynamics (MD) simulations are carried out to investigate the interaction between the selected nanomaterials. It is demonstrated that graphene nanoribbon (GNR) can helically insert into and wrap onto the single-walled carbon nanotube (SWCNT) to form a helical configuration, which has been validated by experimental result. We also find that carbon nanoring (CNR) can be
encapsulated by the hollow interior of the SWCNTs to form a DNA-like double-helix, or collapse to a spiral double graphitic nanoribbon around SWCNT. The GNR and CNR can spontaneously scroll around the metallic nanowires (NWs) in a spiral manner to fabricate the core/shell composites. We
numerically study the spiral nucleation mode of silicon solidified on the surface of carbon nanocones (CNC) and SWCNT. Furthermore, the interacting mechanism and thermodynamic model are also built to investigate the spiral arrangement of nanomaterials. It is speculated that spiral conformation takes the least amount of energy and takes up the least space. In experiment, the polar-surface and the screw dislocation can be acted as a driving force to induce intrinsic helicity of crystal. Despite the enormous researches of the spiral growth, exhaustive follow-up studies are also needed to explain the mechanism clearly.

全文: [PDF]
中图分类号: O47
关键词: 纳米材料;螺旋生长;分子动力学模拟;碳纳米管;石墨烯纳米带;石墨烯纳米环
Nanomaterials; helical growth; molecular dynamics (MD) simulations; carbon nanotube;