Piezoelectric Polymers

Due to their sensitivity, flexibility, and tunable impedance, electret polymers are of interest for sensing, actuating, and energy harvesting applications.  We are interested in accurately detecting and harvesting energy from the sounds and vibrations of the human body.  To improve the sensitivity and impedance matching of electret polymers for  a target of interest, we take a collaborative approach employing contributions from the Mechanical and Materials Engineering, Chemistry, and Electrical and Computer Engineering Departments.  We present several different, but complimentary, areas of research that span from material design to device fabrication:

(1) Development of novel electret materials by increasing the inherent polarity of charge-stabilizing dielectric multilayers and optimizing the porosity of highly hydrophobic statically chargeable polymers
(2) Use of nucleic acids to perform in-situ poling of piezoelectric polymers
(3) Synthesis and 3D printing of soft piezoelectric composites with tunable acoustic impedance
(4) Demonstration that the piezoelectric response of electro spun polyvinylidene fluoride (PVDF) is overwhelmed by the electrostatic response caused by trapped and triboelectric charges under certain conditions
(5) Fabrication of a flexible hybrid energy harvester device that combines piezoelectric and electrostatic contributions to enhance harvested energy per volume

While our current work focuses on capturing sounds from the human body, we envision that this work will also be relevant to underwater and airborne sensing applications and for energy harvesting.