Computational Study of Low Interlayer Friction in Tin+1Cn (n = 1, 2, and 3) MXene.
Difan ZhangMichael AshtonAlireza OstadhosseinAdri C T van DuinRichard G HennigSusan B SinnottPublished in: ACS applied materials & interfaces (2017)
The friction of adjacent Tin+1Cn (n = 1, 2, and 3) MXene layers is investigated using density functional theory (DFT) calculations and classical molecular dynamics simulations with ReaxFF potentials. The calculations reveal the sliding pathways in all three MXene systems with low energy barriers. The friction coefficients for interlayer sliding are evaluated using static calculations. Both DFT and ReaxFF methods predict friction coefficients between 0.24 and 0.27 for normal loads less than 1.2 GPa. The effect of titanium (Ti) vacancies in sublayers and terminal oxygen (O) vacancies at surfaces on the interlayer friction is further investigated using the ReaxFF potential. These defects are found to increase the friction coefficients by increasing surface roughness and creating additional attractive forces between adjacent layers. However, these defective MXenes still maintain friction coefficients below 0.31. We also consider functionalized Ti3C2 MXene terminated with -OH and -OCH3 and find that compared to the -O-terminated surface both groups further reduce the interlayer friction coefficient to 0.10-0.14.
Keyphrases
- molecular dynamics simulations
- density functional theory
- molecular docking
- molecular dynamics
- solar cells
- lymph node metastasis
- escherichia coli
- squamous cell carcinoma
- single cell
- genome wide
- atomic force microscopy
- risk assessment
- magnetic resonance imaging
- dna methylation
- diffusion weighted imaging
- quantum dots
- computed tomography
- biofilm formation