Origin of Nanoscale Friction Contrast between Supported Graphene, MoS2, and a Graphene/MoS2 Heterostructure

• DOI: 10.1021/acs.nanolett.9b02035
• Publication Date: 2019-07-03T11:02:39Z
• Authors: Mohammad R. Vazir...; Han Ye; Zhijiang Ye; Alberto Otero-de-...; Meng-Qiang Zhao; Zhaoli Gao; A. T. Charlie Joh...; Erin R. Johnson; Robert W. Carpick; Ashlie Martini
• Keywords: Nanoscale friction; heterostructure; 02 engineering and technology; Condensed Matter Physics; molecular dynamics; graphene versus MoS; Engineering; graphene versus MoS2; Physical Sciences; atomic force microscope; Nanotechnology; Nanoscience & Nanotechnology; density-functional theory; 0210 nano-technology

Ultralow friction can be achieved with 2D materials, particularly graphene and MoS2. The nanotribological properties of these different materials have been measured in previous atomic force microscope (AFM) experiments sequentially, precluding immediate direct comparison their frictional behavior. Here, is characterized at the nanoscale using AFM same tip sliding over graphene, MoS2, a graphene/MoS2 heterostructure single measurement, repeated hundreds times, also slowly varying normal force. material systems are simulated molecular dynamics (MD) analyzed density functional theory (DFT) calculations. In both MD simulations, consistently exhibits lower than MoS2 monolayer heterostructure. some cases, on that monolayer. Quasi-static simulations DFT calculations show origin contrast difference energy barriers for across each three surfaces.