THERMOELECTRIC BEHAVIOR IN LEAD SELENIDE NANOCRYSTAL FILMS

Author(s): Ly, Alvin | Advisor(s): Hochbaum, Allon I | Abstract: Thermoelectric power generation could be crucial in a sustainable energy future through waste heat energy recycling. Typical nanoengineering of thermoelectric materials requires energy intensive and expensive methods of device fabrication. We employ a facile solution processed device fabrication method that can easily be scaled up for manufacturing while maintaining its cost effectiveness. In this work, we establish and qualify a thermopower measurement system for thin film and bulk devices. To qualify the measurement system, we show that trends in the signs and magnitudes of the Seebeck coefficients of known silicon standards are correct. We also show that PbSe nanocrystal thin film devices exhibit a large Seebeck coefficient (~1500-2000 μV/K) prior to alumina infilling and a reduced Seebeck coefficient (~800-1200 μV/K) post alumina infilling. With this measurement tool, we are able to view differences in thermopower before and after atomic layer deposition treatment within an oxygen-free atmosphere.