The project has advanced the field of organic electrochemical transistors (OECTs) and organic mixed ionic–electronic conductors (OMIECs) by combining synthesis, characterization, modelling, device engineering and application development. New synthetic routes were established to produce defect-free conjugated polymers, significantly improving OECT performance and providing benchmark materials for the consortium. A wide range of small-molecule and polymeric OMIECs were developed, including ion-selective small-molecule systems and conjugated microporous polymers with tunable architectures. Complementary to the synthetic efforts, multiscale modelling revealed detailed mechanisms of ion-charge interactions in thin-films and guided molecular design strategies towards chemical structures and morphologies yielding the optimal balance between hydrophilic and hydrophobic interactions and maximizing the product µC*, while advanced spectroscopic and structural methods deepened the understanding of electronic and ionic transport.
These material insights enabled innovative device concepts. Blending strategies were introduced to overcome the scarcity of ambipolar OMIECs, achieving multifunctional devices with superior capacitance, mobility, and operational flexibility. Improvements in printing and manufacturing platforms allowed the transition from depletion-mode to accumulation-mode OECTs, enabling low-power complementary circuits. Novel OECT-based circuits were further integrated into conformable systems for bioelectronic applications. Parallel work established validation pipelines, extending the potential impact of OECTs to brain–computer interfaces and EEG monitoring.
Overall, the project has provided a rational framework for OMIEC design, advanced the technological maturity of OECTs, and demonstrated their relevance for sensing, signal processing, and neurotechnology. Dissemination has been extensive, through high-impact publications, conference presentations, and patent application, ensuring strong visibility and paving the way for future exploitation