Due to the widespread use of nanocarbon materials (NCMs), more researchers are studying their tribological performances. In this work, the tribological behaviors of the following five types of NCMs with different geometric shapes were evaluated in a novel oil-in-water system: spherical fullerenes (C60, 0D), tubular multi-walled carbon nanotubes (MWCNT, 1D), sheet graphene oxide (GO, 2D), sheet graphene oxide derivative (Oct-O-GO, 2D), and lamellar graphite (G, 3D). Among these, GO with two types of oxidation degrees, i.e., GO(1), GO(2), and Oct-O-GO(1) were synthesized and characterized using Fourier-transform infrared spectroscopy, Raman spectroscopy, x-ray diffraction, thermogravimetric analysis, scanning electron microscopy, and contact angle measurements. The load-carrying capacity of the NCM emulsions were evaluated using a four-ball test machine, and the lubrication performances were investigated using a high-frequency reciprocating friction and wear tester with a sliding distance of 1,800 mm under different loads (50 N and 100 N) at 0.5 Hz. The results revealed that the Oct-O-GO(1) emulsion exhibited the best load-carrying capacity, and the best friction-reducing and anti-wear properties compared to other emulsions. Moreover, the anti-wear advantage was more prominent under high load conditions, whereas the other emulsions exhibited a certain degree of abrasive or adhesive wear. The lubrication mechanism was determined through the analysis of worn surfaces using scanning electron microscopy/energy-dispersive x-ray spectroscopy, micro-Raman spectroscopy, and x-ray photoelectron spectroscopy. The results revealed that during frictional sliding, the ingredients in the emulsion can absorb and react with the freshly exposed metal surface to form surface-active films to protect the surfaces from abrasion. Moreover, it was found that the higher the amount of ingredients that contain alkyl and O-H/C=O, the better was the lubrication performance in addition to an increase in the carbon residue in the tribofilm generated on the meal surface.

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纳米碳材料在水性体系中的摩擦学行为

由于纳米碳材料（NCM）的广泛使用，越来越多的研究人员正在研究其摩擦学性能。在这项工作中，在新型水包油系统中评估了以下五种具有不同几何形状的NCM的摩擦学行为：球形富勒烯（C60，0D），管状多壁碳纳米管（MWCNT，1D），片状石墨烯氧化物（GO，2D），片状石墨烯氧化物衍生物（Oct-O-GO，2D）和层状石墨（G，3D）。其中，利用傅里叶变换红外光谱，拉曼光谱，X射线衍射对具有两种氧化度的GO（GO（1），GO（2）和Oct-O-GO（1））进行了合成和表征。 ，热重分析，扫描电子显微镜和接触角测量。使用四球试验机评估NCM乳液的承载能力，并使用高频往复摩擦磨损测试仪（在50 N和100 N下滑动距离为1800 mm）研究润滑性能N）在0.5 Hz下 结果表明，与其他乳液相比，Oct-O-GO（1）乳液表现出最佳的承载能力，最佳的减摩和抗磨性能。此外，在高负荷条件下，抗磨损优势更为突出，而其他乳液则表现出一定程度的磨料或粘合剂磨损。通过使用扫描电子显微镜/能量分散x射线光谱，显微拉曼光谱和x射线光电子能谱分析磨损表面来确定润滑机理。结果表明，在摩擦滑动过程中，乳液中的成分可以吸收并与刚暴露的金属表面发生反应，形成表面活性膜，从而保护表面免受磨损。此外，发现包含烷基和OH / C ＝ O的成分的量越高，除了在膳食表面上产生的摩擦膜中的碳残留增加之外，润滑性能也越好。