When 3:30 PM - 5:00 PM Oct 18, 2013
Where 1670 Beyster Building
Add event to calendar vCal
iCal

Ferecrystals: New Materials with Designed Nanoarchitecture and Tunable Properties


David C. Johnson
University of Oregon, Materials Science Institute and Department of Chemistry

We have developed a synthetic approach to new materials that uses composition control on an Angstrom length scale to control solid-state reaction pathways, leading to the self-assembly of new nanostructured compounds consisting of two or more compounds with different crystal structures that are interleaved on the nanoscale.  By avoiding compounds on equilibrium phase diagrams, we have prepared hundreds of new metastable compounds with designed nanostructure, including structural isomers. Many of these materials have unprecedented physical properties, including the lowest thermal conductivities ever reported for a fully dense solid, systematic structural changes dependent on nanostructure, and unusual electrical behavior.  We believe the ability to prepare entire families of new nanostructured compounds and equilibrating them to control carrier concentrations permits a new "thin film metallurgy" or “nanochemistry” in which nanostructure and composition can both be used to tailor physical properties, interfacial structures can be determined for precisely defined constituent thicknesses, and interfacial phenomena and modulation doping can be systematically exploited. 

More information about this event…