Analytical diffusiophoretic mobility solution of rigid colloids in a non-Newtonian power-law fluid

We derive diffusiophoretic mobility expressions for a rigid colloidal particle suspended in a non-Newtonian power-law fluidic medium. Although several investigations have been conducted on the diffusiophoresis of colloids in Newtonian fluids, the same in non-Newtonian fluids remains unexplored and warrants significant attention. Employing a flat-plate geometry suitable for an electric double layer that is much thinner than the particle size, a semianalytic mobility solution is deduced for arbitrary particle charge. Subsequently, closed-form expressions are obtained for weakly charged particles. Results show that rigid particles move faster in shear-thinning fluids and slower in shear-thickening fluids compared to Newtonian fluids.