Author ORCID Identifier
https://orcid.org/0009-0003-0420-9864
Date Available
12-19-2026
Year of Publication
2025
Document Type
Doctoral Dissertation
Degree Name
Doctor of Philosophy (PhD)
College
Engineering
Department/School/Program
Materials Science and Engineering
Faculty
Alexandra F. Paterson
Faculty
Matthew Weisenberger
Faculty
Matthew Beck
Abstract
The field of organic bioelectronics is rapidly evolving as we move away from traditional rigid electronics toward more flexible devices that could be seamlessly integrated with biological tissues. These technologies rely on materials that can interact with the human body and environment while enabling real-time monitoring of different stimuli. Organic mixed ionic-electronic conductors (OMIECs), a subclass of organic semiconductors, are especially promising due to their ability to couple ionic and electronic transport.
This research advances OMIEC-based devices through two complementary processing strategies: electronic fibers and 3D printing, both using poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS), a widely studied OMIEC valued for its stability and processability. Among the many platforms enabled by OMIECs, organic electrochemical transistors (OECTs) stand out for their low-voltage operation, high sensitivity to environmental changes, and compatibility with biological systems.
First, PEDOT:PSS fibers were fabricated and used as the active channel material in OECTs. The fiber spinning process induced chain alignment, which, combined with contact engineering, yielded record-high charge carrier mobility. Their axon-like geometry further enabled dopamine sensing for bio-hybrid applications. In addition, to advance neuromorphic functionality, we also investigated ionic-electronic coupling within fiber-OECTs, providing new insights into the design of next-generation devices for neuromorphic computing. Beyond neuromorphic devices, the conductivity and flexibility of PEDOT:PSS fibers were utilized in fully textile-based pressure sensors. By sewing interdigitated electrodes from PEDOT:PSS yarns and, for the first time, producing PEDOT:PSS nonwovens, we created durable pressure sensors that were integrated into a robotic arm, enabling real-time pressure monitoring and safe object handling.
In parallel, PEDOT:PSS-based inks were developed for additive manufacturing, allowing direct 3D printing of electrodes onto flexible substrates. This platform enabled the fabrication of electrodes for OECTs and organic microelectrode arrays (OMEAs), with future applications in neural activity monitoring.
Altogether, these fiber-based and 3D printed strategies offer a cost-effective and customizable way to scalable device fabrication and lay the foundation for a new generation of organic bioelectronics. The insights gained into ion–electron interactions, material design, and scalable processing open pathways toward wearable health monitors, neuromorphic circuits, smart textiles, and brain–machine interfaces. By bridging the gap between living systems and electronic technologies, this work advances both the fundamental understanding and real-world applications of bioelectronics.
Digital Object Identifier (DOI)
https://doi.org/10.13023/etd.2025.618
Funding Information
This study was supported by the National Science Foundation under Cooperative Agreement No. 1849213. Any opinions, findings, conclusions, or recommendations expressed in this material are those of the authors and do not necessarily reflect the views of the National Science Foundation.
This work was also supported by an IMPACT Award from the Office of the Provost, University of Kentucky.
Recommended Citation
Alarcon Espejo, Paula, "FUNCTIONAL FIBER-BASED AND 3D-PRINTED PEDOT:PSS DEVICES FOR WEARABLE BIOELECTRONICS AND NEUROMORPHIC APPLICATIONS" (2025). Theses and Dissertations--Chemical and Materials Engineering. 184.
https://uknowledge.uky.edu/cme_etds/184
Included in
Electronic Devices and Semiconductor Manufacturing Commons, Materials Chemistry Commons, Polymer and Organic Materials Commons, Semiconductor and Optical Materials Commons
