Efficacy of self-phoretic colloids and microswimmers

Abstract

Within a unified formulation, encompassing self-electrophoresis, self-diffusiophoresis, and self-thermophoresis, we provide a simple integral kernel transforming the relevant surface flux to particle velocity for any spheroid with axisymmetric surface activity and uniform phoretic mobility. We define efficacy, a dimensionless efficiency-like quantity expressing the speed resulting from unit absolute flux density on the surface, which allows a meaningful comparison of the performance of different motor designs. For bipartite designs with piecewise uniform flux over complementary surface regions, the efficacy is mapped out over the entire range of geometry (discotic through sphere to rod-like) and of bipartitioning, and intermediate aspect ratios that maximize efficacy are identified. Comparison is made to experimental data from the literature.

References in corpus (5)

• Active Motion of Janus Particle by Self-thermophoresis in Defocused Laser Beam
• Designing phoretic micro- and nano-swimmers
• Collective Thermotaxis of Thermally Active Colloids
• Phoretic Motion of Spheroidal Particles Due To Self-Generated Solute Gradients
• Nonlinear, electrocatalytic swimming in the presence of salt

Cited by in corpus (11)

• Tuning the motility and directionality of self-propelled colloids
• Geometric tuning of self-propulsion for Janus catalytic particles
• Self-propulsion near the onset of Marangoni instability of deformable active droplets
• Spiral diffusion of rotating self-propellers with stochastic perturbation
• The Efficiency of Self-Phoretic Propulsion Mechanisms with Surface Reaction Heterogeneity
• Shape dependent phoretic propulsion of slender active particles
• Bypassing slip velocity: rotational and translational velocities of autophoretic colloids in terms of surface flux
• Diffusiophoretic propulsion of an isotropic active colloidal particle near a finite-sized disk embedded in a planar fluid-fluid interface
• Jerky chiral active particles
• The autophoretic torus
• Extrapolation theory for Stokes flow past a deformed sphere