2023/09/20 by Dolachai Boniface, Sergi G. Leyva, Boniface, Dolachai +5
Engineering · Physics and Astronomy · #FOS: Physical sciences #Micro and Nano Robotics #Microfluidic and Bio-sensing Technologies #Orbital Angular Momentum in Optics #Soft Condensed Matter (cond-mat.soft)
paper · pdf · doi:10.48550/arxiv.2309.11084
openalex publication_date 2023/09/20 · openalex created_date 2023/09/22 · openalex updated_date 2026/07/30
Active particles driven by a chemical reaction are the subject of intense research to date due to their rich physics, being intrinsically far from equilibrium, and their multiple technological applications. Recent attention in the field is now shifting towards exploring the fascinating dynamics of mixture of active and passive systems. Here we realize active colloidal rafts, composed of a single catalytic particle encircled by several shells of passive microspheres assembled via light activated, chemophoretic flow. We show that considering only diffusiophoresis can explain the cluster kinetics but not the cluster propulsion behavior. Thus, using the Lorenz reciprocal theorem, we show that propulsion emerges by considering hydrodynamics via the diffusioosmotic answer of the substrate to the generated chemophoretic flow. While diffusioosmotic flows are often relegate to a secondary role, our work demonstrates their importance to understand the rich physics of active catalytic systems.