Reversible emulsification controlled by ionic surfactants and responsive nanoparticles

Abstract

We identify a new mechanism for the spontaneous formation of an oil-in-water emulsion. Our classical density functional, which describes electrostatics, ionic surface reactions, and nanoparticle adsorption, predicts kinetically and even thermodynamically stable emulsion droplets with a tunable mesoscopic size. Our results closely match recent experiments [S. Sacanna et al., Phys. Rev. Lett., 2007, 98, 158301 and D. Kraft et al., J. Phys. Chem. B, 2010, 114, 10347], and may open new pathways for the reversible dispersion of particle-coated droplets that are desired in the fields of catalysis, controlled drug delivery and particle synthesis