T K Sham

Department of Chemistry
University of Western Ontario
London Ontario Canada

The advancement in synthesis of nanoscaled materials as well as characterization methodologies provides a wonderful playground to test and understand the electronic behavior of these materials, which usually behave quite differently from their bulk counter parts and can have profound implications to the development of new technologies, such as nanodevices, catalysts and sensors, just to name a few. In this talk, the morphology, structure and electronic behavior of a number of prototype nanoparticles (NP) and nanowires (NW) will be described. Systems of interest include Au NPs and related noble metal NPs, porous silicon and silicon NW, compound semiconductor nanowires, ZnO, ZnS, CdSe, etc. and hetero-structures, as well as nanoparticles of carbon and silicon. Preparation strategies leading to the formation of nanoparticles and nanowires of desired size and morphology will be described together with investigations using electron microscopy and x-ray spectroscopy with synchrotron radiation, among other techniques. Of particular interest is the size-dependent light emitting properties of these materials. A new technique, x-ray excited optical luminescence in energy and time domain, the latter takes advantage of time structure of the synchrotron, will be introduce to illustrate another powerful methodology in nanomaterials analysis.