Chen Zhongliang, Dong Xiaohu, Chen Zhangxin
State Key Laboratory of Petroleum Resources and Prospecting, China University of Petroleum (Beijing), Beijing 102249, China.
J Chem Phys. 2021 Feb 21;154(7):074505. doi: 10.1063/5.0038869.
Carbon nanotubes (CNTs) have a wide range of applications in nanotechnology engineering. This research aims to quantify the effect of wall vibration on n-decane molecules' diffusion in double-walled CNTs (DWNTs) with different diameters and determine the diffusion mechanisms behind it. Molecular dynamics simulations are performed to generate mass density profiles of confined n-decane molecules. The root mean square fluctuation and mean squared displacement analyses show that the confinement suppresses n-decane molecules' fluctuations. A self-diffusion coefficient of n-decane molecules in a 13.6 Å-diameter DWNT is the largest. However, the vibration enhancement of the n-decane molecules' diffusion in a 27.1 Å-diameter DWNT is 207%, more extensive than that in 13.6 Å-diameter and 10.8 Å-diameter DWNTs. The n-decane-CNT attractive interactions, extreme confinement, and surface friction affect the n-decane molecules' diffusion in CNTs with vibration.
碳纳米管（CNTs）在纳米技术工程中有广泛的应用。本研究旨在量化壁振动对不同直径双壁碳纳米管（DWNTs）中正癸烷分子扩散的影响，并确定其背后的扩散机制。进行分子动力学模拟以生成受限正癸烷分子的质量密度分布。均方根涨落和均方位移分析表明，受限作用抑制了正癸烷分子的涨落。正癸烷分子在直径为13.6 Å的双壁碳纳米管中的自扩散系数最大。然而，正癸烷分子在直径为27.1 Å的双壁碳纳米管中的扩散振动增强率为207%，比直径为13.6 Å和10.8 Å的双壁碳纳米管中的增强更为显著。正癸烷与碳纳米管的吸引相互作用、极端受限作用和表面摩擦力会影响振动作用下正癸烷分子在碳纳米管中的扩散。
