Colloidal Nanoparticle Catalysis for Enzyme Site Mimics
Our research targets the preparation of ligand-capped metal nanoparticles that are active catalysts for regio-, chemo-, and/or stereo-selective organic reactions. The main objective is to investigate the effects of the surface density and structure/functionality/conformation of thiolate ligands adsorbed on metal nanoparticle catalyst surfaces. This work is building upon our recently reported synthetic method generating stable Pd nanoparticles capped with a low density of alkanethiolate ligands. These Pd nanoparticles were synthesized using S-alkylthiosulfates as a source of protecting ligands and shown to exhibit a unique selectivity for organic reactions such as the isomerization of various allyl alcohols to the corresponding carbonyl compounds and the selective hydrogenation of alkenes in the presence of other reactive functional groups. [Funded by NIH-SCORE]
Nanoparticle-Nanodisc Hybrids for Multifunctional Theranostics
The development of a simple and safe way to detect and cure diseases has been considered as a high priority area in the field of biotechnology and medical research. Our research specifically targets the preparation of biocompatible nanoparticle platform for multifunctional diagnostics and therapeutic agents (hyperthermia treatment guide) for tumor cells. The target nanocarriers are the dendron-conjugated gold nanoparticles (Den-AuNP) and dendron-conjugated gold nanoparticle-graphene oxide hybrids (Den-AuGO) containing drug molecules, cancer specific targeting groups, and plasmonic theranostic agents. Both Den-AuNP and Den-AuGO are composed of nontoxic materials and will resist aggregation in biological fluids due to the presence of biocompatible dendron shells. Cancer specific targeting groups will guide them specifically to the tumor sites. In addition, Au nanoparticles or nanorods can be locally heated by irradiating visible to near IR lights and act as local heat sources that can destroy tumor tissues by hyperthermia or initiate chemotherapy by releasing adsorbed drug molecules.
Engineered Nanoparticle Hybrids as Energy Materials
Our research targets the preparation of hybrid nanostructured materials that are suitable for catalysis applications. The solid support materials such as nanocarbons and topological insulators with unique physical and chemical properties are considered as promising candidates for enhancing adsorption of organic molecules and catalytic efficiency of adjoining nanoparticulate materials. The main objective is to investigate the effects of nanoparticle core size and shape and solid support composition on catalytic properties of nanoparticle hybrids. [Funded by Keck Foundation]Increased use of engineered nanomaterials has generated a need to define their dynamic behaviors and impacts in physical and chemical properties. The nature and extent of the transformations (e.g. aggregation, dissolution, and migration) must be understood before significant progress can be made toward understanding and predicting device performances. Our research targets the investigation of the thermally induced transformation of Au, Ag, Pd, and bimetallic nanoparticles on two dimensional atomic layered nanostructures. In particular, the effects on the optical and catalytic properties of engineered nanoparticle films will be the focal points of our research.