Complex Nanomaterials via Simple Chemistry

Younan Xia
Georgia Institute of Technology
Thursday, September 27, 2012
NCSU, Room 1007, Engineering Building 1 | 2:15pm

The first documented synthesis of nanocrystals can be traced back to the beautiful work by Michael Faraday in 1856 when he demonstrated the preparation of gold colloids with a ruby color. Ever since, many different methods have been developed for preparing nanocrystals, but essentially all the products were troubled by problems such as irregular shapes, broad size distributions, and poorly defined morphologies. Only within the last decade has it become possible to generate nanocrystals with the quality, quantity, and reproducibility needed for a systematic study on their properties as a function of size, shape, and structure. I will briefly cover some of these developments in this talk, with a focus on solution-phase syntheses of noble-metal nanocrystals. While the synthetic methods only involve simple redox reactions, 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 well-controlled sizes, shapes and properties. The success of these syntheses has enabled us to tailor the plasmonic and catalytic properties of noble-metal nanocrystals for a range of applications including photonics, sensing, imaging, biomedicine, catalysis, and fuel cell technology.