Developing Design Rules for Organic Mixed Ion-Electron Conducting Polymers with Coarse-Grained Molecular Dynamics

Organic mixed ion-electron conducting (OMIEC) polymers exhibit transport of both electrons and ions. This unique functionality underpins many emerging applications such as, biosensors, organic electrochemical transistors, neurocomputing devices, and batteries. OMIEC design is incipient, and the few materials that have been synthesized have been based on electron conducting units and ion conducting units from adjacent applications in organic semiconductors and polymer electrolytes, respectively. Although this modular approach has produced materials exhibiting mixed transport, further progress is frustrated by incomplete knowledge of how ionic and electronic transport are coupled in these materials and the absence of design rules specific to OMIECs. In this work, we develop general coarse-grained model which can effectively explore the slow dynamics and nanoscale features of these systems. The model is extremely flexible and enables variation of backbone anisotropy, persistence length, side-chain density, hydrophilicity, and patterning, that can be used to interrogate how these general properties affect OMIEC behavior and electronic ionic coupling. We present our findings on the emergent OMIEC physics upon variation in sidechain composition and further, suggest novel design rules.