Motivation
The future impact of nanotechnology will depend less on the structures we can fabricate and more on the functions we can engineer. Despite myriad methods for the synthesis of “small” structures, we struggle to direct and control the processes required for the realization of functional systems at colloidal scales (nanometers to microns). By contrast, living organisms harness flows of matter and energy to perform remarkable feats of engineering: they assemble dynamic multiscale materials; they capture and convert energy into complex motions; they regulate tangled networks of chemical reactions; they replicate their structures and processes in exponential fashion. Guided by this inspiration, our research seeks to characterize and control matter outside of thermodynamic equilibrium to enable new materials and technologies with capabilities that rival those of living organisms.
Active Colloidal Materials
Our research focuses on the structure and dynamics of particulate matter (nanocrystals, droplets, etc.) dispersed in liquids with sizes ranging from few nanometers to tens of microns. This scale remains a challenging frontier in material science – often beyond the limits of both top-down fabrication strategies and bottom-up chemical approaches. Materials at these scales offer unique mechanical, electronic, and magnetic properties required by emerging applications in energy capture and storage, photonics, and electronics. It is the challenge of nanoengineering to organize these materials into functional systems best exemplified by the structural and dynamical complexity of living cells. Such complexity cannot be achieved at equilibrium but instead requires flows of matter and energy to enable smart materials capable of actuating, sensing, adapting, self-repairing, and even self-replicating. We use external stimuli (e.g., electric fields, chemical reactions, shear forces) to drive colloidal systems away from equilibrium in order (i) to understand dynamic (dissipative) self-assembly and (ii) to engineer the spontaneous organization of functional materials. Building on our expertise in colloidal interactions, self-assembly, and non-equilibrium phenomena, we integrate experiment with theory and simulation to unlock the mysteries of matter far from equilibrium and realize the full potential of nanotechnology.
Follow the links below to learn more about ongoing research efforts in our lab.
Bayesian Optimal Design
Here, we make use of Bayesian statistics to create a normative framework that automates an observation-inference-design loop to run "optimal" experiments which converge on a set of parameter values given a strong guiding model.
Chemical Reaction Networks
Chemical networks describe the web of intermediates between reactants and products, increasing exponentially with tree depth. In this work, we identify "optimal" reaction pathways to navigate such pathways based on differing criteria - minimizing cost, maximizing energy efficiency, minimizing environmental impact, amongst others.
Colloidal Machines
Biological systems achieve dynamic functions at the macroscale through dissipative processes at the microscale, here we seek to learn the lessons of this distributed actuation mechanism to engineer efficient energy conversion for colloidal materials.
Contact Charge Electrophoresis
Contact Charge Electrophoresis (CCEP) is a novel mechanism of electrophoresis, allowing for the rapid transport of micron sized particles over large length scales with nanowatt power requirements.
Nanoparticle Amphiphiles
Amphiphilic nanoparticles decorated by hydrophobic and hydrophilic ligands can sit at the interface of oil-water systems while retaining their ability to be driven by external fields, thereby creating field-responsive surfactants.