Talk (non-conference) (Invited)

FZJ-2015-02117

http://join2-wiki.gsi.de/foswiki/pub/Main/Artwork/join2_logo100x88.png Near Wall Properties of Colloids Studied by Evanescent Wave

Lang, P. R. (Corresponding Author)FZJ* ; Dhont, J. K. G.FZJ* ; July, C. ; Desio, S.FZJ* ; Holmqvist, P.FZJ* ; Lisicki, M. ; Cichocki, B.

2014

Abstract: Over the last decade we developed instrumental equipment, based onevanescent light scattering, to investigate the static interaction of colloidalparticles with an adjacent wall, as well as the near wall dynamics of theseparticles. In this talk I will give an introduction to the techniques, beforediscussing recent experiments.Using Total internal Reflection Microscopy (TIRM), we investigated thedepletion interaction induced by rod– and disc– shaped particles at rest andunder the influence of flow fields. There we could show that the strength ofthese depletion potentials can be tuned by the applied shear rate.Using Evanescent Wave Dynamic Light Scattering (EWDLS) we studied thedynamics of particles close to a flat interface, providing experimental prove forthe long standing theoretical prediction that particle dynamics near walls areslowed down and are anisotropic. For the first time, we showed thatrotational and translational contributions to the particles near wall dynamicscan be separated experimentally.

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Contributing Institute(s):

1. Weiche Materie (ICS-3)

Research Program(s):

1. 451 - Soft Matter Composites (POF2-451) (POF2-451)
2. ESMI - European Soft Matter Infrastructure (262348) (262348)
3. NANODIRECT - Toolbox for Directed and Controlled Self-Assembly of nano-Colloids (213948) (213948)

Appears in the scientific report 2014

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