Impact of aqueous suspension drops onto non-wettable porous membranes: Hydrodynamic focusing and penetration of nanoparticles

The impacts and dynamic penetration of nanoparticle suspension drops into porous filter membranes are studied experimentally and theoretically. This type of penetration is associated with hydrodynamic focusing and is radically different from the wettability-driven imbibition. In the case of hydrodynamic focusing water can penetrate into a non-wettable porous medium at very low values of the dynamic pressure associated with drop impact. Two …