(43b) Pt-SiO2 Janus Particles Near the Water/Oil Interface : A Competition between Motility and Thermodynamics
AIChE Annual Meeting
Monday, November 16, 2020 - 8:15am to 8:30am
Although various aspects of the behavior of Janus particles near liquid/liquid interfaces have been studied through different experimental and theoretical realizations, the effect of motility on the behavior of Janus particles near liquid/liquid interfaces has not been investigated. In our study, we demonstrate our ability to engineer the behavior of highly interfacially active Janus particles near a water/oil interface by introducing motility to the system. Passive, i.e., non-motile, platinum-capped silica (Pt-SiO2) Janus particles are fabricated using physical vapor deposition. They exhibit a strong tendency to attach to water/oil interfaces with the Pt cap facing the oil and the SiO2 side facing the water phase. In contrast, we show that active, i.e., motile Pt-SiO2 Janus particles in the presence of H2O2, approach the interface, orient in a sideways fashion with the Janus boundary perpendicular to the interface, and then swim in the vicinity of the interface similar to observations reported near solid/liquid interfaces.