中国物理B ›› 2022, Vol. 31 ›› Issue (4): 44704-044704.doi: 10.1088/1674-1056/ac381b

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Diffusion of a chemically active colloidal particle in composite channels

Xin Lou(娄辛)1,2, Rui Liu(刘锐)2,1, Ke Chen(陈科)2,1,3, Xin Zhou(周昕)1,4,†, Rudolf Podgornik1,2,4,‡, and Mingcheng Yang(杨明成)2,1,3,§   

  1. 1 School of Physical Sciences, University of Chinese Academy of Sciences, Beijing 100049, China;
    2 Beijing National Laboratory for Condensed Matter Physics and Key Laboratory of Soft Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China;
    3 Songshan Lake Materials Laboratory, Dongguan 523808, China;
    4 Wenzhou Institute, University of Chinese Academy of Sciences, Wenzhou 325001, China
  • 收稿日期:2021-10-16 修回日期:2021-11-02 接受日期:2021-11-10 出版日期:2022-03-16 发布日期:2022-03-29
  • 通讯作者: Xin Zhou, Rudolf Podgornik, Mingcheng Yang E-mail:xzhou@ucas.ac.cn;rudipod@gmail.com;mcyang@iphy.ac.cn
  • 基金资助:
    Project supported by the National Natural Science Foundation of China (Grant Nos. 11874397, 11674365, and 11774393) and the Strategic Priority Research Program of the Chinese Academy of Sciences (Grant No. XDB33000000).

Diffusion of a chemically active colloidal particle in composite channels

Xin Lou(娄辛)1,2, Rui Liu(刘锐)2,1, Ke Chen(陈科)2,1,3, Xin Zhou(周昕)1,4,†, Rudolf Podgornik1,2,4,‡, and Mingcheng Yang(杨明成)2,1,3,§   

  1. 1 School of Physical Sciences, University of Chinese Academy of Sciences, Beijing 100049, China;
    2 Beijing National Laboratory for Condensed Matter Physics and Key Laboratory of Soft Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China;
    3 Songshan Lake Materials Laboratory, Dongguan 523808, China;
    4 Wenzhou Institute, University of Chinese Academy of Sciences, Wenzhou 325001, China
  • Received:2021-10-16 Revised:2021-11-02 Accepted:2021-11-10 Online:2022-03-16 Published:2022-03-29
  • Contact: Xin Zhou, Rudolf Podgornik, Mingcheng Yang E-mail:xzhou@ucas.ac.cn;rudipod@gmail.com;mcyang@iphy.ac.cn
  • Supported by:
    Project supported by the National Natural Science Foundation of China (Grant Nos. 11874397, 11674365, and 11774393) and the Strategic Priority Research Program of the Chinese Academy of Sciences (Grant No. XDB33000000).

摘要: Diffusion of colloidal particles in microchannels has been extensively investigated, where the channel wall is either a no-slip or a slip-passive boundary. However, in the context of active fluids, driving boundary walls are ubiquitous and are expected to have a substantial effect on the particle dynamics. By mesoscale simulations, we study the diffusion of a chemically active colloidal particle in composite channels, which are constructed by alternately arranging the no-slip and diffusio-osmotic boundary walls. In this case, the chemical reaction catalyzed by the active colloidal particle creates a local chemical gradient along the channel wall, which drives a diffusio-osmotic flow parallel to the wall. We show that the diffusio-osmotic flow can significantly change the spatial distribution and diffusion dynamics of the colloidal particle in the composite channels. By modulating the surface properties of the channel wall, we can achieve different patterns of colloidal position distribution. The findings thus propose a novel possibility to manipulate colloidal diffusion in microfluidics, and highlight the importance of driving boundary walls in dynamics of colloidal particles in microchannels.

关键词: diffusion, composite channels, diffusio-osmotic flow, hydrodynamic effect

Abstract: Diffusion of colloidal particles in microchannels has been extensively investigated, where the channel wall is either a no-slip or a slip-passive boundary. However, in the context of active fluids, driving boundary walls are ubiquitous and are expected to have a substantial effect on the particle dynamics. By mesoscale simulations, we study the diffusion of a chemically active colloidal particle in composite channels, which are constructed by alternately arranging the no-slip and diffusio-osmotic boundary walls. In this case, the chemical reaction catalyzed by the active colloidal particle creates a local chemical gradient along the channel wall, which drives a diffusio-osmotic flow parallel to the wall. We show that the diffusio-osmotic flow can significantly change the spatial distribution and diffusion dynamics of the colloidal particle in the composite channels. By modulating the surface properties of the channel wall, we can achieve different patterns of colloidal position distribution. The findings thus propose a novel possibility to manipulate colloidal diffusion in microfluidics, and highlight the importance of driving boundary walls in dynamics of colloidal particles in microchannels.

Key words: diffusion, composite channels, diffusio-osmotic flow, hydrodynamic effect

中图分类号:  (Complex fluids and colloidal systems)

  • 47.57.-s
66.10.cd (Thermal diffusion and diffusive energy transport) 02.70.Ns (Molecular dynamics and particle methods)