title: Tribotronic control of friction in oil-based lubricants with ionic liquid additives.
abstract: Atomic force microscopy (AFM) reveals that tribotronic control of friction using an external potential applied to a gold surface is possible for ionic liquid (IL) concentrations as low as 5 mol% in hexadecane. The IL used is trihexyl(tetradecyl)phosphonium bis(2,4,4-trimethylpentyl)phosphinate, in which both the cation and anion have surfactant-like structures, and is miscible with hexadecane in all proportions. For IL concentrations less than 5 mol% friction does not vary with applied potential, but for 5 mol% and above changing the potential changes the composition of the IL boundary layer from cation-enriched (negative potentials) to anion-enriched (positive potentials). As the lubricities of the cation-rich and anion-rich boundary layers differ, this enables active control of friction in oil-based lubricants.
authors: Priority Research Centre for Advanced Fluids and Interfaces, Newcastle Institute for Energy and Resources, University of Newcastle, Callaghan, NSW 2308, Australia. rob.atkin@newcastle.edu.au.
authors: P K
authors: PK
authors: Cooper
authors: Priority Research Centre for Advanced Fluids and Interfaces, Newcastle Institute for Energy and Resources, University of Newcastle, Callaghan, NSW 2308, Australia. rob.atkin@newcastle.edu.au.
authors: H
authors: H
authors: Li
authors: KTH Royal Institute of Technology, School of Chemical Science and Engineering, Department of Chemistry, SE-100 44 Stockholm, Sweden and SP Technical Research Institute of Sweden, SP Chemistry, Materials and Surfaces, SE-114 86 Stockholm, Sweden.
authors: M W
authors: MW
authors: Rutland
authors: Priority Research Centre for Advanced Fluids and Interfaces, Newcastle Institute for Energy and Resources, University of Newcastle, Callaghan, NSW 2308, Australia. rob.atkin@newcastle.edu.au.
authors: G B
authors: GB
authors: Webber
authors: Priority Research Centre for Advanced Fluids and Interfaces, Newcastle Institute for Energy and Resources, University of Newcastle, Callaghan, NSW 2308, Australia. rob.atkin@newcastle.edu.au.
authors: R
authors: R
authors: Atkin