Hostname: page-component-cd9895bd7-gxg78 Total loading time: 0 Render date: 2024-12-26T17:58:27.554Z Has data issue: false hasContentIssue false

Wall effects on self-diffusiophoretic Janus particles: a theoretical study

Published online by Cambridge University Press:  24 October 2013

Darren G. Crowdy*
Affiliation:
Department of Mathematics, Imperial College London, 180 Queen’s Gate, London SW7 2AZ, UK
*
Email address for correspondence: [email protected]

Abstract

We present a theoretical investigation of the self-diffusiophoresis of a class of two-faced, two-dimensional Janus particles propelled by the production of gradients in the concentration of a solute diffusing into a surrounding fluid at zero Reynolds and Péclet numbers. Those concentration gradients produce a tangential boundary slip resulting in translation and rotation of the particle, as a consequence of the fact that it is free of both force and torque. The model Janus particles studied here have piecewise constant surface mobilities and surface activities over two faces. An isolated circular Janus particle is studied first and its speed of locomotion in free space is found analytically. Confinement effects are then investigated by placing such a Janus particle near a straight no-slip wall. The governing nonlinear dynamical system is found in explicit form. It is used to study how the geometry, location and orientation of the particle relative to the wall affect its motion. It is found that if the particles do not hit the wall in finite time they are eventually repelled away from it.

Type
Papers
Copyright
©2013 Cambridge University Press 

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

Ablowitz, M. & Fokas, A. S. 1997 Complex Variables: Introduction and Applications. Cambridge University Press.Google Scholar
Anderson, J. L. 1989 Colloid transport by interfacial forces. Annu. Rev. Fluid Mech. 21, 6199.Google Scholar
Crowdy, D. G. 2008 The Schwarz problem in multiply connected domains and the Schottky–Klein prime function. Complex Var. Elliptic Equ. 53, 221236.Google Scholar
Crowdy, D. G. 2011 Treadmilling swimmers near a no-slip wall at low Reynolds number. Intl J. Non-Linear Mech. 46, 577585.CrossRefGoogle Scholar
Crowdy, D. G. & Or, Y. 2010 Two-dimensional point singularity model of a low-Reynolds-number swimmer near a wall. Phys. Rev. E 81, 036313.CrossRefGoogle ScholarPubMed
Crowdy, D. G. & Samson, O. 2010 Hydrodynamic bound states of a low-Reynolds-number swimmer near a gap in a wall. J. Fluid Mech. 666, 721740.Google Scholar
Ebbens, S. J. & Howse, J. R. 2010 In pursuit of propulsion at the nanoscale. Soft Matt. 6, 726738.Google Scholar
Gangwal, S., Cayre, O. J., Bazant, M. Z. & Velev, O. D. 2008 Induced-charge electrophoresis of metallodielectric particles. Phys. Rev. Lett. 100, 058302.Google Scholar
Golestanian, R., Liverpool, T. B. & Ajdari, A. 2005 Propulsion of a molecular machine by asymmetric distribution of reaction products. Phys. Rev. Lett. 94, 220801.Google Scholar
Golestanian, R., Liverpool, T. B. & Ajdari, A. 2007 Designing phoretic micro- and nano-swimmers. New J. Phys. 9, 126.Google Scholar
Jeffrey, D. J. & Onishi, Y. 1981 The slow motion of a cylinder next to a plane wall. Q. J. Mech. Appl. Maths 34, 129137.Google Scholar
Keh, H. J., Horng, K. D. & Kuo, J. 1991 Boundary effects on electrophoresis of colloidal cylinders. J. Fluid Mech. 231, 211228.CrossRefGoogle Scholar
Kilic, M. S. & Bazant, M. Z. 2011 Induced-charge electrophoresis near an insulating wall. Electrophoresis 32, 614628.CrossRefGoogle ScholarPubMed
Lauga, E. & Davis, A. M. J. 2012 Viscous Marangoni propulsion. J. Fluid Mech. 705, 120133.CrossRefGoogle Scholar
Michelin, S., Lauga, E. & Bartolo, D. 2013 Spontaneous autophoretic motion of isotropic particles. Phys. Fluids 25, 061701.CrossRefGoogle Scholar
Miloh, T. 2013 Dipolophoresis of Janus nanoparticles in a microchannel. Electrophoresis 34, 19391949.CrossRefGoogle Scholar
Paxton, W. F., Kistler, K. C., Olmeda, C. C., Sen, A., Angelo, S. K. St., Cao, Y., Mallouk, T. E., Lammert, P. E. & Crespi, V. H. 2004 Catalytic nanomotors: autonomous movement of striped nanorods. J. Am. Chem. Soc. 126, 1342413431.CrossRefGoogle ScholarPubMed
Popescu, M. N., Dietrich, S. & Oshanin, G. 2009 Confinement effects on diffusiophoretic self-propellers. J. Chem. Phys. 130, 194702.Google Scholar
Squires, T. & Bazant, M. Z. 2006 Breaking symmetries in induced charge electro-osmosis and electrophoresis. J. Fluid Mech. 560, 65101.CrossRefGoogle Scholar
Thutupalli, S., Seemann, R. & Herminghaus, S. 2011 Swarming behaviour of simple model squirmers. New J. Phys. 13, 073021.CrossRefGoogle Scholar
Zhao, H. & Bau, H. H. 2007 On the effect of induced electro-osmosis on a cylindrical particle next to a surface. Langmuir 23, 40534063.Google Scholar