MSE Seminar Series: Oded Rabin
Friday, September 21, 2012
1:00 p.m.-2:00 p.m.
Room 2108 Chemical and Nuclear Engineering Bldg.
301 405 5240
Engineered Nanostructures for Plasmonics and Thermoelectrics
Department of Materials Science & Engineering
University of Maryland College Park
Nanostructures, as individual or coupled objects, may display properties that are different from those of macroscopic materials. My research aims at understanding the size dependence of physical properties at the nanoscale, and utilizing the new science for applications in sensing and energy conversion. (a) New strategies for fabrication of plasmonic nanoparticle assemblies will be presented. The investigation of planar assemblies, extending over many cm^2, demonstrated that these large-scale structures are inexpensive and reliable substrates for enhanced Raman spectroscopy (SERS) of thiols. The investigation of linear assemblies, consisting of only a handful of nanoparticles, demonstrated that consistent field-enhancement may be the most important selection criteria when selecting nanoparticle clusters as sub-micron SERS substrates. (b) Current research efforts in Thermoelectrics are focused on exploiting nanostructures for high efficiency conversion of waste heat into electrical energy. Theoretical predictions of enhanced thermoelectric power factor values in low dimensional structures have found limited support in experimental data. I will present our models for thermoelectric transport in nanostructures that show a better match with experiments. These models illustrate that stringent materials design parameters need to be reached to improve the thermoelectric efficiency using nanostructures.