One of the promising approaches to achieving large scale superlubricity is the use of junctions between existing ultra-flat surface together with superlubric graphite mesas.Here we studied the frictional properties of...One of the promising approaches to achieving large scale superlubricity is the use of junctions between existing ultra-flat surface together with superlubric graphite mesas.Here we studied the frictional properties of microscale graphite mesa sliding on the diamond-like carbon,a commercially available material with a ultra-flat surface.The interface is composed of a single crystalline graphene and a diamond-like carbon surface with roughness less than I nm.Using an integrated approach,which includes Argon plasma irradiation of diamond-like carbon surfaces,X-ray photoelectron spectroscopy analysis and Langmuir adsorption modeling,we found that while the velocity dependence of friction follows a thermally activated sliding mechanism,its temperature dependence is due to the desorption of chemical groups upon heating.These observations indicate that the edges have a significant contribution to the friction.Our results highlight potential factors affecting this type of emerging friction junctions and provide a novel approach for tuning their friction properties through ion irradiation.展开更多
基金Wengen Ouyang acknowledges the financial support from a fellowship program for outstanding postdoctoral researchers from China and India in Israeli Universites.Ming Ma wishes to acknowledge the financial support by Thousand Young Talents Program and the NSFC grant Nos.11632009,11772168,and 11890673Quanshui Zheng wishes to acknowledge the financial support by the NSFC grant No.11890671.
文摘One of the promising approaches to achieving large scale superlubricity is the use of junctions between existing ultra-flat surface together with superlubric graphite mesas.Here we studied the frictional properties of microscale graphite mesa sliding on the diamond-like carbon,a commercially available material with a ultra-flat surface.The interface is composed of a single crystalline graphene and a diamond-like carbon surface with roughness less than I nm.Using an integrated approach,which includes Argon plasma irradiation of diamond-like carbon surfaces,X-ray photoelectron spectroscopy analysis and Langmuir adsorption modeling,we found that while the velocity dependence of friction follows a thermally activated sliding mechanism,its temperature dependence is due to the desorption of chemical groups upon heating.These observations indicate that the edges have a significant contribution to the friction.Our results highlight potential factors affecting this type of emerging friction junctions and provide a novel approach for tuning their friction properties through ion irradiation.
