Clickable Janus Particles.

Janus particles are colloidal analogues of molecular amphiphiles that can self-assemble to form diverse suprastructures, exhibit motility under appropriate catalytic reactions, and strongly adsorb to fluid-fluid interfaces to stabilize multiphasic fluid mixtures. The chemistry of Janus particles is the fundamental parameter that controls their behavior and utility as colloid surfactants in bulk solution and at fluid interfaces. To enable their widespread utilization, scalable methods that allow for the synthesis of Janus particles with diverse chemical compositions and shapes are highly desirable. Here, we develop clickable Janus particles that can be modified through thiol-yne click reactions with commercially available thiols. Janus particles are modified to be amphiphilic by introducing either carboxyl, hydroxyl, or amine moieties. We also demonstrate that regulating the extent of the modification can be used to control the particle morphology, and thus the type of emulsion stabilized, as well as to fabricate composite Janus particles through sequential click reactions. Modifying Janus particles through thiol-yne click chemistry provides a fast-reacting, scalable synthesis method for the fabrication of diverse Janus particles.