Assembly and speed in ion-exchange-based modular phoretic microswimmers.
writer：Ran Niu*, Denis Botin, Julian Weber, Alexander Reinmüller, Thomas Palberg.
keywords：modular swimming, speed, assembly
source：期刊
specific source：Langmuir
Issue time：2017年
We report an experimental study on ion-exchange based modular microswimmers in low-salt water. Cationic ion exchange particles and passive cargo particles assemble into self-propelling complexes, showing self-propulsion at speeds of several micrometers per second over extended distances and times. We quantify the assembly and speed of the complexes for different combinations of ion-exchange particles and cargo particles, substrate types, salt types and concentrations, and cell geometries. Irrespective of the experimental boundary conditions, we observe a regular development of the assembly shape with increasing number of cargo. Moreover, the swimming speed increases stepwise upon increasing the number of cargo and then saturates at a maximum speed, indicating the active role of cargo in modular swimming. We propose a geometric model of self-assembly to describe the experimental observations in a qualitative way. Our study also provides some constraints for future theoretical modeling and simulation.
全文鏈接: https://pubs.acs.org/doi/suppl/10.1021/acs.langmuir.7b00288
