(Georgia Institute of Technology, 2007-12-11)
Nair, Sankar
Metal oxide materials offer a vast range of tunable physical and chemical properties, accessible by low-temperature liquid-phase chemistry. In the form of nanoscopic objects, these materials have a variety of potential applications in future nanoscale devices and nanostructured assemblies. Our research over the last 3 years at Georgia Tech has addressed several fundamental questions pertaining to the synthesis of metal oxide nano-objects with complex structure and controllable dimensions. The ultimate objective is to develop a generalizable set of "design rules" to engineer the "shape and size", "curvature", chemical composition, and ordered internal structure of ultra-small nanoscopic objects. In this talk, he described insights into the kinetic and thermodynamic principles underlying the formation of complex nano-objects such as single-walled metal oxide nanotubes whose lengths can be tuned from ultra-short (20 nm) to about 100 nm and whose diameters can be tuned with Angstrom-level precision through manipulation of interatomic potential energies. A proposal is made for a mechanistic paradigm that we refer to as "amorphous nanoparticle condensation followed by internal rearrangement", and some of its broader technological implications were discussed.