구형 및 평면 원자현미경 탐침에 대한 2차원 소재의 마찰 특성
Frictional Properties of Two-dimensional Materials against Spherical and Flat AFM Tips
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초록
Two-dimensional materials such as graphene, h-BN, and MoS2 have attracted increased interest as solid lubricant and protective coating layer for nanoscale devices owing to their superior mechanical properties and low friction characteristics. In this work, the frictional properties of single-layer graphene, h-BN, and MoS2 are experimentally investigated under various normal forces using atomic force microscope (AFM) tips with a spherical and flat end, with the aim to gain a better understanding of frictional behaviors. The nonlinear relationship between friction and normal force friction was clearly observed for single-layer graphene, h-BN, MoS2 specimens slid against the spherical and flat AFM tips. The results also indicate that single-layer graphene, h- BN, MoS2 exhibit low frictional properties (e.g., friction coefficient below 0.1 under 70~100 nN normal force). In particular, graphene is found to be superior to h-BN and MoS2 in terms of frictional properties. However, the friction of single-layer graphene, h-BN, MoS2 against the flat tip is larger than that against the spherical tip, which may be attributed to the relatively large adhesion. Furthermore, it is shown that the fluctuation of friction is more significant for the flat tip than the spherical tip. The resutls of this study may be helpful to elucidate the feasibility of using two-dimensional materials as solid lubricant and protective coating layer for nanoscale devices.
Abstract
Two-dimensional materials such as graphene, h-BN, and MoS2 have attracted increased interest as solid lubricant and protective coating layer for nanoscale devices owing to their superior mechanical properties and low friction characteristics. In this work, the frictional properties of single-layer graphene, h-BN, and MoS2 are experimentally investigated under various normal forces using atomic force microscope (AFM) tips with a spherical and flat end, with the aim to gain a better understanding of frictional behaviors. The nonlinear relationship between friction and normal force friction was clearly observed for single-layer graphene, h-BN, MoS2 specimens slid against the spherical and flat AFM tips. The results also indicate that single-layer graphene, h- BN, MoS2 exhibit low frictional properties (e.g., friction coefficient below 0.1 under 70~100 nN normal force). In particular, graphene is found to be superior to h-BN and MoS2 in terms of frictional properties. However, the friction of single-layer graphene, h-BN, MoS2 against the flat tip is larger than that against the spherical tip, which may be attributed to the relatively large adhesion. Furthermore, it is shown that the fluctuation of friction is more significant for the flat tip than the spherical tip. The resutls of this study may be helpful to elucidate the feasibility of using two-dimensional materials as solid lubricant and protective coating layer for nanoscale devices.
참고문헌 (15)
- Schwierz, F., "Graphene Transistors", Nat. Nano., 5, pp.487~496 (2010)
- Jariwala, D., "Emerging Device Applications for Semiconducting Two-dimensional Transition Metal Dichalcogenides", ACS Nano, 8, pp.1102~1120 (2014)
- Radisavljevic, B., "Single-layer MoS 2Transistors", Nat. Nano., 6, pp.147~150 (2011)
- Tran-Khac, B.C., "Operational and Environmental Conditions Regulate the Frictional Behavior of Two-dimensional Materials", Appl. Surf. Sci., 483, pp.34~44 (2019)
- Cho, D.H, "Effect of Surface Morphology on Friction of Graphene on Various Sub-strates", Nanoscale, 5, pp.3063~3069 (2013)
- Ko, J. H., "Nanotribological Properties of Fluorinated, Hydrogenated, and Oxidized Graphenes", Tribol. Lett., 50, pp.137~144 (2013)
- Lin, L. Y., "Friction and Wear Characteristics of Multi-layer Graphene Films Investigated by Atomic Force Microscopy", Surf. Coat. Tech., 205, pp.4864~4869 (2011)
- Tran-Khac, B. C., "Inter-facial Strength and Surface Damage Characteristics of Atomically Thin h-BN, MoS 2, and Graphene", ACS Appl. Mater. Interfaces, 10, pp.9164~9177 (2018)
- Chung, K.H, "Funda-mental Investigation of the Wear Progression of Sili-con Atomic Force Microscope Probes", Tribol. Lett, 52, pp.315~325 (2013)
- Lee, C., "Anomalous Lattice Vibrations of Single- and Few-Layer MoS 2", ACS Nano, 4, pp.2695~2700 (2010)
- Hutter, J. L., "Calibration of Atomic-force Microscope Tips", Rev. Sci. Instrum, 64, pp.1868~1873 (1993)
- 김류운, "Multiple Pivot loading 방법을 이용한 액체 환경에서의 수평방향 힘 교정", 한국트라이볼로지학회지, 29(2), pp.91~97 (2013), 한국트라이볼로지학회[DOI]
- Gotsmann, B., "Atomistic Wear in a Sin-gle Asperity Sliding Contact", Phys. Rev. Lett., 101, pp.125501-1~125501-4 (2008)
- Grafström, S., "Analysis of Lateral Force Effects on the Topography in Scanning Force Microscopy", J. Vac. Sci. Technol. B: Microelectron. Nanometer Struct. -Process., Meas., Phenom., 12, pp.1559~1564 (1994)
- Mo, Y., T., "Friction Laws at the Nanoscale", Nature, 457, pp.1116~1119 (2009)