van Wijk Merel M, de Wijn Astrid S, Fasolino Annalisa
Radboud University, Institute for Molecules and Materials, Heyendaalseweg 135, 6525 AJ Nijmegen, The Netherlands.
J Phys Condens Matter. 2016 Apr 6;28(13):134007. doi: 10.1088/0953-8984/28/13/134007. Epub 2016 Mar 2.
We investigate solid lubrication of graphene and graphene flakes using atomistic molecular-dynamics simulations. We find that graphene flakes yield lower friction than graphene as a result of a collective mechanism that emerges from the independent behaviour of the flakes. By freezing out different degrees of freedom of the flakes, we are able to attribute the low friction to non-simultaneous slipping of the individual flakes. We also compare the results of the atomistic simulations to those of a simplified two-dimensional model and find that the behaviour of the latter is strongly dependent on parameters, which emerge naturally from the atomistic simulations.
我们使用原子分子动力学模拟研究了石墨烯和石墨烯薄片的固体润滑。我们发现，由于薄片的独立行为产生的集体机制，石墨烯薄片产生的摩擦力低于石墨烯。通过冻结薄片不同程度的自由度，我们能够将低摩擦归因于单个薄片的非同时滑动。我们还将原子模拟的结果与简化二维模型的结果进行了比较，发现后者的行为强烈依赖于从原子模拟中自然出现的参数。
