Anisotropic fluid flows in black phosphorus nanochannels

• Published in: Physical chemistry chemical physics : PCCP 2024-01, Vol.26 (5), p.389-3896
• Main Authors: Jian, Ruda, Wu, Shiwen, Tian, Siyu, Mashhadian, Amirarsalan, Xu, Zhihao, Leonardi, Stefano, Luo, Tengfei, Xiong, Guoping
• Format: Article
• Language: English
• Subjects: Anisotropic fluids; Anisotropy; Dodecane; Fluid flow; Friction; Friction factor; Liquid flow; Molecular dynamics; Nanochannels; Phosphorus; Two dimensional materials; Velocity; Velocity distribution
• ISSN: 1463-9076; 1463-9084
• DOI: 10.1039/d3cp04736a

With the development of advanced micro/nanoscale technologies, two-dimensional materials have emerged from laboratories and have been applied in practice. To investigate the mechanisms of solid-liquid interactions in potential applications, molecular dynamics simulations are employed to study the flow behavior of n -dodecane (C 12 ) molecules confined in black phosphorus (BP) nanochannels. Under the same external conditions, a significant difference in the velocity profiles of fluid molecules is observed when flowing along the armchair and zigzag directions of the BP walls. The average velocity of C 12 molecules flowing along the zigzag direction is 9-fold higher than that along the armchair direction. The friction factor at the interface between C 12 molecules and BP nanochannels and the orientations of C 12 molecules near the BP walls are analyzed to explain the differences in velocity profiles under various flow directions, external driving forces, and nanochannel widths. The result shows that most C 12 molecules are oriented parallel to the flow direction along the zigzag direction, leading to a relatively smaller friction factor hence a higher average velocity. In contrast, along the armchair direction, most C 12 molecules are oriented perpendicular to the flow direction, leading to a relatively larger friction factor and thus a lower average velocity. This work provides important insights into understanding the anisotropic liquid flows in nanochannels. With the development of advanced micro/nanoscale technologies, two-dimensional materials have emerged from laboratories and have been applied in practice.