Ayyagari Aditya V, Mutyala Kalyan C, Sumant Anirudha V
Center for Nanoscale Materials, Argonne National Laboratory, Lemont, IL, 60439, USA.
Sci Rep. 2020 Sep 21;10(1):15390. doi: 10.1038/s41598-020-72666-4.
Conventional solid lubricants such as MoS, graphite, or diamond-like carbon films demonstrate excellent tribological performance but only in specific environments due to their inherent materials properties. This limitation prohibits using these solid lubricants in environments that change dynamically. This study presents the results of a novel solid lubricant that was developed using a combination of solution-processed 2D-molybdenum disulfide and graphene-oxide (GO) that can be deposited on to stainless steel substrates using a simple spray-coating technique and show exceptional performance in multifarious environments namely, ambient (humid) atmosphere, dry nitrogen, and vacuum. The tribological performance of the coatings was evaluated using a ball-on-disc sliding test and demonstrated an excellent wear/friction performance in all environments and coating survived even after 44 km of linear sliding. Transmission electron microscopy and Raman spectroscopy analysis of the tribolayers suggested in-operando friction-induced re-orientation of MoS layers that were protected by GO layers and, an absence of MoO peaks indicate a strong resistance to intercalation with moisture and oxygen. The simplicity and robustness of the hybrid MoS-GO solid lubricant in mitigating wear-friction behavior of steel-on-steel tribopair in a multifarious environment is a game-changing and is promising for various applications.
传统的固体润滑剂，如二硫化钼、石墨或类金刚石碳膜，尽管因其固有材料特性在特定环境中展现出优异的摩擦学性能，但仅适用于特定环境。这种局限性使得这些固体润滑剂无法在动态变化的环境中使用。本研究展示了一种新型固体润滑剂的研究成果，该润滑剂由溶液处理的二维二硫化钼和氧化石墨烯（GO）组合而成，可通过简单的喷涂技术沉积在不锈钢基材上，并在多种环境中表现出卓越性能，即环境（潮湿）大气、干燥氮气和真空环境。通过球盘滑动试验对涂层的摩擦学性能进行了评估，结果表明该涂层在所有环境中均具有出色的磨损/摩擦性能，即使在44公里的线性滑动后涂层依然完好。对摩擦层的透射电子显微镜和拉曼光谱分析表明，在运行过程中，二硫化钼层在氧化石墨烯层的保护下发生摩擦诱导的重新取向，并且没有三氧化钼峰表明对水分和氧气的嵌入具有很强的抗性。在多种环境中，这种混合二硫化钼-氧化石墨烯固体润滑剂在减轻钢-钢摩擦副磨损-摩擦行为方面的简单性和耐用性具有变革性意义，并且在各种应用中具有广阔前景。
