ChBE Seminar Series–Dr. Younan Xia
In addition to its annual lectures, ChBE hosts a weekly seminar throughout the year with invited lecturers who are prominent in their fields. Unless otherwise noted, all seminars are held on Wednesdays in the Molecular Science and Engineering Building ("M" Building) in G011 (Cherry Logan Emerson Lecture Theater) at 4:00 p.m. Refreshments are served at 3:30 p.m. in the Emerson-Lewis Reception Salon.
Putting Chemistry to Work for Nano and Biomedical Research
Nanomaterials are finding widespread use in many applications, including electronics, photonics, information storage, catalysis, as well as diagnosis and treatment of diseases. Chemistry plays a pivotal role in all these exciting developments because it allows for the synthesis of nanomaterials with well-controlled sizes, shapes, compositions, structures, and properties. In this talk, I will demonstrate this concept using a number of examples from my own research group, including silver/palladium nanocubes, gold nanocages, and platinum nanodendrites. While the synthetic methods mainly involve solution-phase redox chemistry, we have been working diligently to understand the complex physics behind the simple chemistry – that is, the nucleation and growth mechanisms leading to the formation of nanocrystals with specific shapes. For example, we have discovered that the shape of metal nanocrystals are dictated by the crystallinity and structure of the seeds, which are, in turn, controlled by factors such as reduction kinetics, oxidative etching, diffusion, and surface capping. The methodologies we have developed seem to work well for all noble metals including silver, gold, palladium, platinum, and rhodium. The success of these syntheses has enabled us to tailor the electronic, plasmonic, and catalytic properties of noble-metal nanocrystals for a range of applications in catalysis and biomedical research.