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arXiv · 2601.00258

Self-diffusiophoretic propulsion in wedge confinement: The role of phoretic interactions

Abdallah Daddi-Moussa-Ider·Ramin Golestanian
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Abstract

We investigate the self-diffusiophoretic motion of a catalytically active spherical particle confined within a wedge-shaped domain. Using the Fourier-Kontorovich-Lebedev transform, we solve the Laplace equation for the concentration field in the diffusion-dominated regime. The method of images is employed to obtain the first and second reflections of the concentration field, accounting for both monopole and dipole contributions of the particle's surface activity. Based on these results, we derive leading-order expressions for the self-induced phoretic velocity in the far-field limit and examine how it varies with the wedge opening angle and the particle's position within the domain. We focus on the contributions to the phoretic velocities arising from phoretic interactions, without accounting for hydrodynamic effects. Our findings reveal that the wedge geometry significantly affects both the magnitude and direction of particle motion. Our study provides a systematic framework for calculating the contributions to the phoretic velocity arising from concentration disturbances near corners, with implications for microfluidic design and control of autophoretic particles in confined geometries.

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Abdallah Daddi-Moussa-Ider, Ramin Golestanian. 2026-01-01. Self-diffusiophoretic propulsion in wedge confinement: The role of phoretic interactions. https://arxiv.org/abs/2601.00258

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