Brownian molecular motors are nanoscale machines that exploit thermal fluctuations for directional motion by employing mechanisms such as the Feynman-Smoluchowski ratchet. In this study, using Non Equilibrium Molecular Dynamics, we propose a novel thermal Brownian motor for pumping water through Carbon Nanotubes (CNTs). To achieve this we impose a thermal gradient along the axis of a CNT filled with water and impose, in addition, a spatial asymmetry by flxing specific zones on the CNT in order to modify the vibrational modes of the CNT. We find that the temperature gradient and imposed spatial asymmetry drive the water ow in a preferential direction. We systematically modified the magnitude of the applied thermal gradient and the axial position of the fixed points. The analysis involves measurement of the vibrational modes in the CNTs using a Fast Fourier Transform (FFT) algorithm. We observed water ow in CNTs of 0.94, 1.4 and 2.0 nm in diameter, reaching a maximum velocity of 5 m/s for a thermal gradient of 3.3 K/nm. The proposed thermal motor is capable of delivering a continuous ow throughout a CNT, providing a useful tool for driving liquids in nanouidic devices by exploiting thermal gradients.
|Title of host publication||Bulletin of the American Physical Society|
|Number of pages||1|
|Publisher||American Physical Society|
|Publication status||Published - 2016|
|Event||69th Annual Meeting of the APS Division of Fluid Dynamics - Portland, United States|
Duration: 20 Nov 2016 → 22 Nov 2016
|Conference||69th Annual Meeting of the APS Division of Fluid Dynamics|
|Period||20/11/2016 → 22/11/2016|
Oyarzua, E., Zambrano, H., & Walther, J. H. (2016). CNT based thermal Brownian motor to pump water in nanodevices. In Bulletin of the American Physical Society (Vol. 61). [A22.00009] American Physical Society.