“Colloids at Fluid Interfaces: Opportunities for Advanced Materials Synthesis”
Ali Mohraz, Associate Professor of Chemical Engineering and Materials Science, University of California, Irvine
Particle sequestration at the interface of immiscible fluids has been known for more than a century and exploited in the formulation of solid-stabilized (Pickering) emulsions for drug delivery, oil recovery, food, and personal care products, to name a few. More recently, new classes of multi-phase mixtures have emerged that exploit interfacial colloid jamming, bridging, ordering, and aggregation for the self-assembly of complex higher-order structures from colloidal building blocks, such as bicontinuous interfacially jammed emulsion gels (bijels), or bridged emulsion gels. The multiphase nature of these mixtures makes them excellent templates for the synthesis of composite materials with tunable morphology at the nano- to micrometer scales, and our group has recently demonstrated various examples of functional materials that can be derived from them. However, to expand these capabilities into a robust materials synthesis platform, the factors that mediate the mechanical stability and processability of these colloidal mixtures must be better understood. In this talk, I will review the fundamentals and recent developments in colloidal self-assembly at fluid interfaces, present a novel materials synthesis route that we have pioneered based on these concepts, and discuss the applications of our technology in electrochemical energy conversion and storage, sensing, catalysis, and tissue engineering. Finally, I will discuss our ongoing efforts to better understand the link between the microstructure, rheology, and processability of this new class of soft materials.
Ali Mohraz received his BSc, ME, and PhD in Chemical Engineering from Azad University, The City College of New York, and The University of Michigan, respectively, and his postdoctoral training at the Frederick Seitz Materials Research Laboratory at The University of Illinois in Urbana-Champaign. He is currently Associate Professor of Chemical Engineering and Materials Science at the University of California, Irvine. Dr. Mohraz’s primary research interests are in colloid science and complex fluids engineering, including colloidal assembly at fluid interfaces and microstructural evolution of complex fluids under transient large-strain deformations.
Additional information: Anna Laromaine