2012-11-13
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Xia, Younan
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.