text: Diffusiophoresis, by definition, moves colloidal particles, and so the applications of diffusiophoresis are to situations where we want to move colloidal particles. Colloidal particles are typically between 10 nanometres and a few micrometres in size. Simple diffusion of colloids is fast on length scales of a few micrometres, and so diffusiophoresis would not be useful, whereas on length scales larger than millimetres, diffusiophoresis may be slow as its speed decreases with decreasing size of the solute concentration gradient. Thus, typically diffusiophoresis is employed on length scales approximately in the range a micrometre to a millimetre. Applications include moving particles into or out of pores of that size, and helping or inhibiting mixing of colloidal particles.
  In addition, solid surfaces that are slowly dissolving will create concentration gradients near them, and these gradients may drive movement of colloidal particles towards or away from the surface. This was studied by Prieve in the context of latex particles being pulled towards, and coating, a dissolving steel surface.