Ultra-low friction of a-C:H films enabled by lubrication of nanodiamond and graphene in ambient air
Ultra-low friction of a-C:H films enabled by lubrication of nanodiamond and graphene in ambient air
复制标题
通过纳米金刚石和石墨烯在环境空气中的润滑实现 a-C:H 薄膜的超低摩擦
DOI：
10.1016/j.carbon.2019.08.010
复制
发表时间：
2019-12-01
期刊：
影响因子：
10.9
通讯作者：
Luo, Jianbin
中科院分区：
文献类型：
--
作者：
Huang, Peng;Qi, Wei;Luo, Jianbin
氢化非晶碳（a- c:H）在环境空气中受到异常高的摩擦，保持超低摩擦状态的可能性仍然是一个巨大的挑战。本文采用纳米金刚石和石墨烯作为固体润滑剂，改善了两种具有代表性的20 at a-C:H薄膜的摩擦学性能。%和40 %。分别为%氢含量。研究结果强调了纳米金刚石+石墨烯复合材料在质量比为1:1、溶液处理浓度为0.1 mg/mL时的协同润滑效果。a-C:H （20 at）的超低摩擦系数接近0.02。更引人注目的是，在a- c:H （40 at）中，COF从0.52急剧降低到0.07。% H)电影。同时，在纳米润滑剂的存在下，两种情况下对应的磨损率都显着降低。其润滑机制主要是基于纳米结构摩擦层的原位生长。讨论了a-C:H膜键合特性和纳米润滑剂摩擦诱导的结构演变在抗磨耐磨摩擦层形成中的作用。这些发现可以丰富对低维纳米润滑剂对a-C:H膜表面改性途径的理解，并有助于开发更具适应性和坚固性的固体碳膜。(C) 2019 Elsevier Ltd.版权所有。
Hydrogenated amorphous carbon (a-C:H) is subjected to abnormal high friction in ambient air, and the possibility to retain an ultra-low friction state remains as a great challenge. Here, nanodiamond and graphene were used as solid lubricants to improve the tribological properties of two representative types of a-C:H films with 20 at.% and 40 at.% hydrogen contents, respectively. The results emphasize the exceptionally synergetic lubrication effect of nanodiamond + graphene composite with a mass ratio of 1:1 and a solution-processed concentration of 0.1 mg/mL. An ultra-low friction coefficient of similar to 0.02 was achieved for a-C:H (20 at.% H) film, and more strikingly, a dramatic reduction in COF from 0.52 to 0.07 was realized in a-C:H (40 at.% H) film. Meanwhile, the wear rates of the counterparts in both cases are significantly reduced in the presence of nano-lubricants. The lubricity mechanisms are mainly based on the in-situ growth of nanostructured tribolayers. The roles of a-C:H film bonding characteristic and the tribo-induced structural evolution of nano-lubricants in the build-up of anti-friction and wear-resistant tribolayers are discussed. These findings can enrich the understanding of surface modification pathways to a-C:H films via low-dimensional nano-lubricants and help to develop more adaptive and robust solid carbon films. (C) 2019 Elsevier Ltd. All rights reserved.