Water-Soluble Graphene Quantum Dots as High-Performance Water-Based Lubricant Additive for Steel/Steel Contact
Water-Soluble Graphene Quantum Dots as High-Performance Water-Based Lubricant Additive for Steel/Steel Contact
复制标题
水溶性石墨烯量子点作为钢/钢接触的高性能水基润滑添加剂
DOI：
10.1007/s11249-019-1177-4
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发表时间：
2019-06-01
影响因子：
3.2
通讯作者：
Yang, Shengrong
中科院分区：
文献类型：
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作者：
Qiang, Ruibin;Hu, Lifang;Yang, Shengrong
在这项工作中，首先通过一种简单的水热法合成了石墨烯量子点（GQDs），然后首次评估了其作为水基润滑剂添加剂的摩擦学性能。通过透射电子显微镜进行的形态观察表明，可以获得平均直径约为2纳米的均匀且单分散的GQDs。傅里叶变换红外光谱和X射线光电子能谱表征表明，所制备的GQDs上存在大量亲水基团，包括羟基、环氧基和羰基，这使得GQDs在水中具有良好的分散性。此外，通过Optimol - SRV - IV往复摩擦试验机研究了其摩擦学性能，结果表明，添加适量的GQDs可以大幅降低水的摩擦系数和磨损率。因此，与氧化石墨烯相比，在相对较低的浓度下，GQD在提高水的摩擦学性能方面更有效。当GQDs水分散液的浓度为4mg/mL时，相应的GQDs - 4样品表现出优异的摩擦学性能，与水相比，摩擦系数降低了42.5%，磨损率降低了58.5%。这些良好的性能表明，所制备的GQDs可作为一种新型的水基润滑剂添加剂，极大地提高水的摩擦学性能。
In this work, graphene quantum dots (GQDs) were firstly synthesized via a simple hydrothermal route and then its tribological performances as water-based lubricant additive were evaluated for the first time. The morphological observation by transmission electron microscope indicates that uniform and monodispersed GQDs with a mean diameter of about 2 nm can be obtained. Fourier transfer infrared spectroscopy and X-ray photoelectron spectroscopy characterizations demonstrate that there are abundant hydrophilic groups existed on the as-prepared GQDs including hydroxyl, epoxy, and carbonyl groups, endowing GQDs with good dispersibility in water. Moreover, the tribological performances are investigated by optimal-SRV-IV reciprocation friction tester, and the results indicated that both the friction coefficient and the wear rate of water can be largely reduced through adding the appropriate amount of GQDs. As a result, compared with graphene oxide, GQD was more effective to enhance the tribological performances of water at the relatively low concentration. When the concentration of GQDs aqueous dispersion is 4 mg/mL, the corresponding sample of GQDs-4 shows the excellent tribological performances with a 42.5% reduction of friction coefficient and a 58.5% decrease of wear rate compared with those of the water. These promising performances demonstrate that the prepared GQDs can be employed as a novel water-based lubricant additive to greatly enhance the tribological performances of the water.