Our research centers on the development of new chemistry, physics, and technological applications of nanomaterials -- a novel class of materials with sizes <100 nm. Innovative technologies are emerging from nanomaterials and nanodevices that will improve the way we live just as microtechnology has done over past several decades.

1. Putting Chemistry to Work for Nanomaterial Synthesis

This research focuses on a long-standing problem in chemistry and physics -- understanding and control of the nucleation/growth steps involved in the chemical synthesis of nanomaterials. We aim to bring revolutionary advances to this field  by developing new tools capable of capturing, identifying, and quantifying the clusters that serve as a bridge between atomic species and nanostructures. This research requires the integration of chemical synthesis, theoretical modeling, cluster speciation using mass spectrometry and electron microscopic analysis. It will provide an atomistic picture of the evolution pathway from atoms to clusters and nanostructures, as well as the design rules for synthesizing metal and semiconductor nanomaterials with well-controlled electronic, magnetic, catalytic and optical properties. The ultimate goal of this work is to build a scientific base for large-scale production of nanomaterials with the specific properties sought for applications in areas such as electronics, photonics, catalysis, information storage, optical sensing, biomedical research.

2. Putting Nanomaterials to Work for Biomedical Research

Because of their small sizes and unique properties, nanomaterials are finding widespread use in studying complex biological systems. This work aims to advance biomedical research by developing new tools and methods based on functional nanomaterials. Our current efforts include development of gold nanocages as contrast agents for optical imaging (e.g., optical coherence tomography, photoacoustic tomography, and two-photon luminescence), and as photothermal agents for therapeutic treatment. We are exploring the use of gold nanocages and other metal nanostructures as substrates for SERS- and LSPR-based detection. We are developing nanoscale capsules by integrating gold nanocages with smart polymers for targeted delivery and controlled release with superb spatial and temporal resolutions. We are applying electrospun nanofibers to neural tissue engineering, drug release, and surface modification. We are also designing new colloidal particles with superparamagnetic features for separation, detection, manipulation, and  tracking of biological species and cellular events. All these research activities will contribute to the emerging field known as nanomedicine.

3. Putting Nanomaterials to Work for Environmental Research

Nanomaterials also hold the key to the continuous progress toward a cleaner environment and sustainability. We aim to demonstrate the fabrication of functional nanomaterials with optimized properties for  a range of related applications. For example, we are exploring the use of nanomaterials for improving the performance of  solar cells, fuel cells, catalytic converters, and water-splitting devices. This research requires a superb understanding of the structure-property relationship that guides the design and synthesis of nanomaterials with well-controlled sizes and shapes for specific applications.