2016/02/09 by Juliane Simmchen, Jaideep Katuri, William E. Uspal +4 · 409 citations
Chemistry · Engineering · Materials Science · Physics and Astronomy · #Biological system #Biology #Chemical physics #Chemistry #Colloid #Janus #Materials science #Micro and Nano Robotics #Microfluidic and Bio-sensing Technologies #Microfluidics #Nanotechnology #Physics #Pickering emulsions and particle stabilization #cond-mat.soft
paper · pdf · doi:10.1038/ncomms10598
published in Nature Communications 7(1), 10598 (Nature Portfolio) · 18 pages, 12 figures
openalex publication_date 2016/02/09 · arxiv created 2016/02/12 · arxiv updated 2016/02/15 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05
Achieving control over the directionality of active colloids is essential for their use in practical applications such as cargo carriers in microfluidic devices. So far, guidance of spherical Janus colloids was mainly realized using specially engineered magnetic multilayer coatings combined with external magnetic fields. Here we demonstrate that step-like submicrometre topographical features can be used as reliable docking and guiding platforms for chemically active spherical Janus colloids. For various topographic features (stripes, squares or circular posts), docking of the colloid at the feature edge is robust and reliable. Furthermore, the colloids move along the edges for significantly long times, which systematically increase with fuel concentration. The observed phenomenology is qualitatively captured by a simple continuum model of self-diffusiophoresis near confining boundaries, indicating that the chemical activity and associated hydrodynamic interactions with the nearby topography are the main physical ingredients behind the observed behaviour.