Research Fields

• Ferroelectret polymers: new concepts for piezoelectric sensors and actuators
• High-Temperature Proton Exchange Membrane Fuel Cells: In collaboration with CMU's Department of Chemistry and Biochemistry and the Department of Mathematics. Development, modeling and characterization of a new class of proton-transporting membranes.
• Non-destructive 3D space-charge and polarization tomography
• Polymer-dispersed liquid crystals with ferroelectric host polymers
• Microscopic mechanisms of charge storage in electret polymers
• Photo- and thermally stimulated discharge currents in charge-storing fluorinated and cycloolefin polymers

Current Research Projects

• Anhydrous Proton Exchange Membranes for High-Temperature Hydrogen Fuel Cells A key component of hydrogen fuel cells is the proton exchange membrane (PEM), which facilitates the movement of protons from the anode to the cathode. Current PEMs rely on water and acidic conditions, limiting the operating temperature to 80 °C, while hydrogen fuel cells perform best at 150-180 °C. This research aims to develop a dry and thermally stable PEM from linear and branched fluoroaromatic polymers with imidazole groups for proton conduction, allowing the PEM to perform at higher temperatures without flooding.
• Dielectric barrier discharges in ferroelectret polymers: Ferroelectrets (i.e., charged cellular polymers) are rendered piezoelectric by means of barrier discharges inside the air-filled voids. Unlike traditional piezoceramics, they are mechanically flexible and can be manufactured to cover large areas. However, much remains to be learned about the microscopic processes of charging and charge-trapping. Achieving this goal requires a multi-technique approach, combining spectroscopic plasma diagnostics with space-charge mapping and electromechanical characterization techniques.
• Non-destructive 3D space-charge and polarization tomography: The ability to accurately and non-destructively measure polarization and space-charge distributions is of prime importance in the research on electrets and organic electronics. Applications include the accumulation of space charge in high-voltage cable insulations, the development and optimization of pyroelectric and piezoelectric sensors, and basic research into the mechanisms of charge storage in electret polymers.