Abstract

Organic mixed ionic/electronic conductors (OMIECs) have gained considerable interest in bioelectronics, power electronics, circuits and neuromorphic computing. These organic, often polymer-based, semiconductors rely on a combination of ionic transport, electronic transport, and high volumetric charge storage capacity. These properties enable new capabilities; for example, in the realm of bioelectronics, OMIEC-based electrochemical devices can efficiently amplify local bio-signals and can be engineered for spiking behavior to mimic basic neural pathways promising efficient biohybrid systems. However, despite recent progress and a rapidly expanding library of new materials, a full understanding of fundamental processes of OMIECs remains elusive. Critically, useful studies require us to probe these systems in device-relevant conditions, fully considering the effects of ions and solvent on microstructure and transport. To this end, we report on recent efforts towards structure/composition-property relations in high performance organic mixed conductors using operando techniques. For example, using resonant scattering and molecular dynamics simulations, we find ion condensation at semiconducting backbones at high charge densities. Such characterization opens new avenues to understand and design more stable, high-performance materials and devices.

Biography

Jonathan Rivnay is a Professor in the Department of Biomedical Engineering and Department of Materials Science and Engineering at Northwestern University. Jonathan earned his B.Sc. in 2006 from Cornell University. He then moved to Stanford University where he earned a M.Sc. and Ph.D. in Materials Science and Engineering, studying the structure and electronic transport properties of organic electronic materials. In 2012, he joined the Department of Bioelectronics at the Ecole des Mines de Saint-Etienne in France as a Marie Curie post-doctoral fellow, working on conducting polymer-based devices for bioelectronics. Jonathan spent 2015-2016 as a member of the research staff in the Printed Electronics group at the Palo Alto Research Center (PARC, a Xerox Co.) before joining the faculty at Northwestern in 2017. He is a recipient of the early career awards from the Office of Naval Research, the National Science Foundation (CAREER), the Alfred P. Sloan Foundation, and is a fellow of the American Institute for Medical and Biological Engineering (AIMBE).