Response of chemically active dimer motor in phase-separating binary fluid mixture: Motility regulation and self-aggregation

The design of synthetic chemically powered nanomotors often considers the fuel and product to be miscible. The propulsion properties of such motors can be altered if the binary fluid consisting of fuel and product is phase separating. The dynamical properties of a dimer motor in a phase-separating binary mixture are discussed. Depending on the strength of phase separation and the activity of the dimer, the single-motor propulsion velocity either decreases or reverses its direction. The velocity reversal is shown to be related to the generated fluid flow around the motor. The collective dynamics of the motors in such phase-separating fluid results in the formation of self-assembled structures.