HydroCat · Understanding the Collective Behaviour of Catalytically-Driven, Self-Propelled Colloids: From Fine-Grained Hydrodynamic Simulations to Effective Field-Theoretical Descriptions

HydroCat proposes a simulation and theory study into the collective behaviour of catalytically-driven, self-propelled colloids. The first step of the investigation focusses on understanding the mechanism by which platinum-coated Janus particles self-propel on a single-particle level. This will be accomplished by modelling the two candidates for the mechanism, self-diffusiophoresis and self-electrophoresis, and directly comparing the behaviour of the hybrid-model to experimental results. Once sufficient insight has been achieved, the focus of the project will shift to the description of the collective behaviour of these particles. Here, HydroCat follows a three-pronged strategy: (i) development of a finely-resolved lattice-Boltzmann (LB) simulation that takes into account all relevant physical effects and is capable of simulating a large number of particles; (ii) coarse-grained molecular dynamics simulations to study the collective behaviour of these Janus colloids, which are benchmarked against the fine LB simulations; and (iii) a fully coarse-grained, field-theoretical description that uses input from both (i) and (ii). HydroCat will result in an improved understanding of the catalytic self-propulsion, which will serve as a solid foundation for the description of experiments and the development of applications.