PhD Defense: “Non-Traditional Study of Renewable Generators in Thermoelectric and Pieoelectric Meta Structures.” April 9, 2018, at 12 PM

David Montgomery, PhD Candidate
Public Presentation in Olin 107
Monday, April 9, 2018, at 12:00 PM
David L. Carroll, PhD, Advisor

The defense will follow.


This work focuses on the combination of thermoelectric and piezoelectric materials into a new hybrid generator. It was discovered that a hybrid thermoelectric piezoelectric generator results in a meta-structure that creates a coupling field effect at the interface between the thermoelectric and piezoelectric films that produces more power than the sum of the individual generators. This coupling field effect causes a modification of the thermoelectric properties causing an observed 468% increase in total power output. In addition to this coupling effect, the first functional thermoelectric and piezoelectric generator design is presented. This is achieved by integrating a flexible continuous alternating p- and n-type semiconductor thermoelectric generator into the electrode of the piezoelectric film.  This design overcomes major issues previously preventing the two materials to be combined in a single generator architecture. This functional thermoelectric piezoelectric generator can achieve 89% of the theoretical thermoelectric power and 540% increase in the piezoelectric power due to the geometry of the structure. A spray doping synthesis method is presented that was used to create the continuous alternating p- and n-type semiconductor film. Spray doping achieves that same thermoelectric properties of solution doping but greatly simplifies the fabrication of a thermoelectric generator. Finally an optimized thermoelectric generator is presented that overcomes many of the current issues plaguing other thin film designs. The optimized structure is robust and is compatible with numerous synthesis methods and materials used in thin film thermoelectrics.