Jiang Q G, Zhang J F, Ao Z M, Wu Y P
College of Mechanics and Materials, Hohai University, Nanjing 210098, China.
Centre for Clean Energy Technology, School of Mathematical and Physical Sciences, University of Technology Sydney, PO Box 123, Broadway, Sydney, NSW 2007, Australia.
Sci Rep. 2015 Oct 26;5:15734. doi: 10.1038/srep15734.
The interface stability of hybrid silicene/fluorosilicene nanoribbons (SFNRs) has been investigated by using density functional theory calculations, where fluorosilicene is the fully fluorinated silicene. It is found that the diffusion of F atoms at the zigzag and armchair interfaces of SFNRs is endothermic, and the corresponding minimum energy barriers are respectively 1.66 and 1.56 eV, which are remarkably higher than the minimum diffusion energy barrier of one F atom and two F atoms on pristine silicene 1.00 and 1.29 eV, respectively. Therefore, the thermal stability of SFNRs can be significantly enhanced by increasing the F diffusion barriers through silicene/fluorosilicene interface engineering. In addition, the electronic and magnetic properties of SFNRs are also investigated. It is found that the armchair SFNRs are nonmagnetic semiconductors, and the band gap of armchair SFNRs presents oscillatory behavior when the width of silicene part changing. For the zigzag SFNRs, the antiferromagnetic semiconducting state is the most stable one. This work provides fundamental insights for the applications of SFNRs in electronic devices.
通过密度泛函理论计算研究了混合硅烯/氟硅烯纳米带(SFNRs)的界面稳定性,其中氟硅烯是完全氟化的硅烯。研究发现,F原子在SFNRs的锯齿形和扶手椅形界面处的扩散是吸热的,相应的最小能垒分别为1.66和1.56 eV,这明显高于原始硅烯上一个F原子和两个F原子的最小扩散能垒,分别为1.00和1.29 eV。因此,通过硅烯/氟硅烯界面工程提高F扩散势垒,可以显著增强SFNRs的热稳定性。此外,还研究了SFNRs的电子和磁性性质。研究发现,扶手椅形SFNRs是非磁性半导体,当硅烯部分的宽度变化时,扶手椅形SFNRs的带隙呈现振荡行为。对于锯齿形SFNRs,反铁磁半导体状态是最稳定的状态。这项工作为SFNRs在电子器件中的应用提供了基本的见解。