Super‐Elasticity and Ultralow Friction of Hydrogenated Fullerene‐Like Carbon Films: Associated with the Size of Graphene Sheets

Abstract

such as high-hardness/strength, excellent elasticity, and high compressibility. [1][2][3][4] Carbon nitride films, [5] pure carbon films, [6] and hydrogenated carbon films [7] containing these fullerene-like structures have been proved to possess excellent elastic recovery rate (85%, 80%, and 85%, respectively) and high hardness values (60, 53, and 19 GPa, respectively). In particular, hydrogenated fullerene-like carbon (FLC:H) films can also exhibit ultralow friction behaviors, which are desirable to minimize mechanical dissipation. These properties are essential for the application of these materials as protective coatings to engineering components. But the exact relationship between these properties and the fullerene-like structures is still unclear. The nanostructure of graphene sheets and the number of cross-linking sites between them may be two main structural factors determining these properties. Exploring the structureproperties relationship is crucial to effectively tailor these properties for potentially more applications. Some relevant studies have demonstrated that fullerene-like spheroids (FLS) encased in disordered graphene layers [4] and aligned carbon nanotube films [8] can display a lot of mechanical characteristics similar to those of architectured materials. Controlling the size, concentration, and connectivity of FLS or manipulating buckled morphologies of nanotube can tailor their mechanical properties. Thus, it is expected that FLC films may yield exceptional and tunable mechanical properties by controlling the nanostructure of graphene sheets. However, there are very few experimental reports on these issues, because designing and controlling the nanostructure of graphene sheets in FLC films remains a technical challenge.Recently a number of methods, such as ion beam-assisted deposition, molecular beam epitaxy, and plasma enhanced chemical vapor deposition (PECVD) have been developed for manufacturing high quality graphene-like materials. [9][10][11] It has been demonstrated that low-energy argon ions bombardment in these deposition systems is beneficial for the formation of graphene network. [12][13][14] Molecular dynamics simulations experiments also showed that low-energy (10-25 eV) argon ions bombardment could result in an increase in the number of graphitic rings and further enhance the graphene network growth. [13,15] The formation of curved graphene sheets (CGS) in magnetron-sputtered CN x films was mainly attributed to Hydrogenated fullerene-like carbon (FLC:H) films would be a widely used material with a unique combination of properties including high-hardness/ strength, excellent elasticity, and ultralow friction. The nanostructure of graphene sheets and the number of cross-linking sites between them may be two main structural factors determining these properties. Exploring the structure-properties relationship is crucial to effectively tailor these properties for potentially more applications. In this study it is demonstrated that FLC:H films can yield exceptional and tunable mec...

Simultaneous production and functionalization of hexagonal boron nitride nanosheets by solvent-free mechanical exfoliation for superlubricant water-based lubricant additives

“…37 Our previous work has demonstrated that the high elasticity of a film is beneficial to the superlow friction. 39,40 Figure 4d and Fig. S7 show the mechanical properties of the wear tracks with and without the Pebax-BNNS/water dispersion as a lubricant.…”

[2 + 1] Cycloaddition reactions of fullerene C60 based on diazo compounds

“…The exceptional physicochemical properties of the fullerene family and, above all, its main representative, C 60 , predetermine the broad practical interest in the use of these compounds. This is quite understandable: compounds with unique optical [ 2 – 4 ], electrophysical [ 5 – 7 ], mechanical [ 8 – 10 ], tribological [ 11 – 13 ], sorption [ 14 – 17 ], and biological properties [ 18 – 20 ], and even new dyes and catalysts [ 21 – 25 ], have already been discovered among functionalized fullerenes.…”

Perspectives of the Friction Mechanism of Hydrogenated Diamond-Like Carbon Film in Air by Varying Sliding Velocity

“…Previously, lots of experimental studies on the tribological properties of DLC films have been carried out by investigating the effects of intrinsic properties, i.e., hydrogen concentration, hardness, metal/nonmetal doping, and so on [8][9][10][11]. However, the tribological properties of DLC films depend on not only the intrinsic parameters, but also many extrinsic factors, such as sliding velocity, normal load, environment atmosphere, and properties of friction interfaces [12][13][14][15].…”