Our current research can be classified into the following sub-groups:
- Electrocatalysis
- Protein therapeutics
- Subsurface nanotechnology
- Gold imaging nanoclusters
Presented below is a summary of research. For further information, please look at the presentation here.
Materials Chemistry for Advanced Functional Metal and Metal Oxide Nanoparticles
We are developing synthetic concepts to control nucleation, growth and passivation of metal and metal oxide nanoparticles in solution with ligands and polymeric stabilizers to design advanced functional materials. The goal is to achieve the proper balance of fundamental science to guide combinatorial materials science to achieved desired function for subsurface energy, electrochemical energy storage, drug delivery and bionanotechnology applications.
Nanoclusters Assembled from Nanoparticles
Organic (proteins) and inorganic (metals and metal oxides) nanoparticles may be assembled into nanoclusters with control of particle size and morphology to design a wide range of novel materials with desired properties. The size and morphology are controlled by tuning colloidal interactions and nucleation and growth pathways. Often the particles are quenched with polymeric stabilizers that may also be used to tailor interfacial properties and other types of functionality.
Nanoparticles at Liquid and Solid Interfaces
The ability to tune the interfacial properties of nanoparticles at either liquid, gas or solid interfaces, in many cases with other amphiphiles including surfactants and polymers, is of broad interest in many fields. For liquid and gas interfaces, we are investigating emulsions and foams. Interactions at solid interfaces are of interest to understand nanoparticle transport in porous media, and nanoparticle adsorption and dispersion of nanoparticles on electrocatalyst supports. The adsorption of covalent grafting of polymers to nanoparticle surfaces is of great interest for modifying the interfacial properties and in some cases rheological behavior.
Nanotechnology in Subsurface Green Energy Production
Even modest changes in greener recovery of oil and gas will have a profound impact on the energy picture and health of the planet, including water utilization. We are developing a new field of subsurface nanotechnology for CO2 sequestration, improved oil recovery, imaging reservoirs, greener fracturing with low water utilization and treatment of marine oil spills. This interdisciplinary research is based combining materials chemistry for nanoparticle synthesis, colloid and interface science for various liquid and solid interfaces, polymer science for stabilization and rheological aspects, and nanoparticle transport. We interact closely with several petroleum engineers in these projects.
Materials Chemistry for Energy Storage: Electrocatalysis, Batteries, and Supercapacitors
Highly active metal and metal oxide electrocatalysts for batteries and supercapacitors are synthesized by arrested growth precipitation methods to control composition, morphology and crystallinity. These catalysts are highly active for the oxygen reduction and oxygen evolution reactions, crucial reactions for bifunctional air electrodes in rechargeable metal-air batteries and in hydrogen production. We use insights into oxide surfaces and crystal structure to design earth-abundant catalysts that could potentially replace costly precious metals and their alloys.
Protein Stabilization and Drug Delivery with Reversible Nanoclusters
One of the grand challenges in drug delivery is for patients to self-administer biopharmaceuticals, including monoclonal antibodies, at home with subcutaneous injection. We are enabling such treatments by forming low viscosity dispersions of protein nanoclusters formed by colloidal assembly. The nanocluster assembly is reversible back to individual biologically active protein molecules. We are attempting to demonstrate that this concept is universal and may be applied to a wide range of proteins. This project combines molecular thermodynamics of protein interactions, colloid science and rheology with studies of protein stability.
Biomedical Imaging/therapy with Biodegradable Nanoclusters
Metal nanoparticles with surface plasmon resonance (SPR) in the near-infrared region (NIR) are of great interest for imaging and treatment of cancer and other diseases. We are designing Au plasmonic nanoclusters via colloidal self-assembly that biodegrade to individual primary particles small enough for kidney clearance. The surface plasmon resonance of the Au particles in the NIR region is being investigated in terms of the cluster morphology based on a variety of techniques. Upon biodegradation of polymer stabilizers, the nanoclusters reversible dissociate to primary particles small enough for clearance through the kidneys.