PHOTOCHEMICAL SYNTHESIS OF 
METAL NANOPARTICLES AND COMPOSITE NANOMATERIALS

Metal nanoparticles with tailored sizes possess many unique optical and electronic properties that make them useful for applications such as catalysis and sensing. While many chemical synthetic routes to these types of nanomaterials exist, femtosecond laser reduction of metal salt precursors has the advantages of avoiding the use of environmentally damaging reducing agents and organic surfactants that can limit the practical use of the resulting materials. Combining metal-salt reduction with laser ablation of a solid surface immersed in the solution enables the synthesis of additional composite nanomaterials with metastable phases.

Current projects include controlling metal salt reduction kinetics and metal nanoparticle sizes using hydroxyl radical scavengers, synthesizing ultrasmall metal-oxide and metal-carbon nanocomposite catalysts from metal salt and organometallic precursors, and depositing metal nanoparticles onto silicon laser-induced periodic surface structures (LIPSS) for surface-enhanced Raman spectroscopy (SERS) sensing applications. Future work will focus on extending these synthetic techniques to earth-abundant metals such as Fe, Co, and Ni.

​

RIGHT NOW PROJECTS

1. Femtosecond reactive laser ablation in liquid (fs-RLAL) is a synthesis approach to generate silica-supported copper oxide nanoparticles (SiO2-CuOx NPs). Investigating the experimental parameters to optimize the catalytic activity toward para-nitrophenol (PNP) and CO2 reduction, and understanding the relationship between the solution composition and the product morphology using TEM, XPS, and SEM-EDX.

2. Laser photochemical reduction (LPR) is used to generate palladium nanoparticles (PdNPs) that have high catalytic activity toward PNP and Fischer Tropsch reactions. We are investigating the laser-induced chemical reactions that leading to different PdNP morphologies by monitoring the PdNP formation rates, and characterizing the PdNPs using TEM imaging.