Bicontinuous Interfacially Jammed Emulsions (Bijels) in Geometrical Confinement
As our fundamental understanding of bijel systems in bulk has matured over the years, some researchers are now interested in exploring the effects of geometrical confinement on bijel morphology. Geometrical confinement introduces two influencing factors of note: (1) interactions with an external surface or surfaces and (2) a reduction in available volume in one or more dimensions. This chapter reviews this emerging sub-topic in the field of bijel research, including a relevant survey of surface-directed spinodal decomposition, as well as the experimental and theoretical studies to date that focus on bijels in geometrical confinement. Current studies have revealed interesting and technologically relevant bijel systems in thin-film and spherical droplet formats. Yet, the scope of this sub-topic field is far from being fully explored, with rich possibilities for varying the interactions with confining surfaces, as well as the bijel composition and finally the nature of the geometrical confinement, all of which can potentially lead to unique morphologies and applications.