Bijels Containing Magnetic Particles: A Simulation Study

Bicontinuous, interfacially jammed emulsion gels (bijels) represent a class of soft solid materials in which interpenetrating domains of two immiscible fluids are stabilized by an interfacial colloidal monolayer. Such structures can be formed by arrested spinodal decomposition from an initially single-phase colloidal suspension. Here we explore by lattice Boltzmann simulation the possible effects of using magnetic colloids in bijels. This may allow additional control over the structure, during or after formation, by application of a magnetic field or field gradient. These effects are modest for typical parameters based on the magnetic nanoparticles used in conventional ferrofluids, although significantly larger particles might be appropriate here. Field gradient effects, which are cumulative across a sample, could then allow a route for controlled breakdown of bijels as they do for particle-stabilized droplet emulsions.