Ion conducting block copolymers (BCEs) have emerged as a promising solution to overcome the inverse relationship between high ionic conductivity and high mechanical robustness required for safer and cheaper electrochemical devices (e.g. batteries, fuel cells, desalination membranes). To date, many studies have investigated the structure and electrochemical property relationship at the membrane scale (>100µm) which is orders of magnitude larger in comparison to the natural periodicity of BCEs (<100nm). This results in a mismatch in the resolution of information that is extracted from AC impedance spectroscopy (EIS) and structure characterization methods. In comparison to the collected structure information, EIS probes the complex impedance response of charge conduction pathways as a function of perturbation frequency. This granularity of the information extracted from EIS to date is far superior to the resolution achieved through thick film structure characterization methods. Our objective is to control and characterize deterministic structure of ion conduction pathways to fully extract information out of electrochemical characterization methods such as AC impedance spectroscopy. The approach is as follows. First, we will study our system in the thin film ($\textless$ 100 $nm$). With the use of thin film self-assembly techniques and directed self-assembly techniques such as chemoepitaxy and graphoepitaxy, the morphology of the BCEs can be structured so that the morphology on the free surface is projected throughout the thin film. This enables simple top down characterization techniques such as scanning electron microscopy and atomic force microscopy to probe deterministic structure. Second, we will study the thin films on top of interdigitated electrodes (IDEs) that enable thin films to be characterized for both structure and complex electrochemical behavior. Third, the IDEs are fully fabricated using CMOS compliant methods that are compatible with nanoscale fabrication methods such as electron beam lithography used to control morphology of BCEs, therefore IDEs can be customized with nanoscale features enabling us to control morphologies on top of the IDEs.



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