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The implementation of dynamic windows that possess electronically tunable transparency is a promising method to increase the energy efficiency of buildings. Long-term dynamic window cyclability is a key issue that has prevented the widespread adoption of many different device architectures. In this manuscript, we have developed an inexpensive (less than $1,000) optoelectronic cycler to improve dynamic window durability testing. The cycler is programmed to process transmission data to dynamically adjust the voltage profile used for window switching throughout the course of long-term cycling experiments. We demonstrate that this optoelectronic cycler results in significantly improved cycle lives for three different dynamic window chemistries that facilitate reversible metal electrodeposition. Taken together, these results showcase a new tool for the dynamic window research community to improve device cyclability in the laboratory setting. 

Robust multivalent ion interaction in electrodes is a grand challenge of next-generation battery research. In this manuscript, we design molecularly-precise nanographene cathodes that are coupled with metallic Zn anodes to create a new class of Zn-ion batteries. Our results indicate that while electrodes with graphite or flat nanographenes do not support Zn-ion intercalation, the larger intermolecular spacing in a twisted peropyrene enables peropyrene electrodes to facilitate reversible Zn-ion intercalation in an acetonitrile electrolyte. While most previous Zn-ion batteries utilize aqueous electrolytes, the finding that nonaqueous Zn electrolytes can support intercalation in nanographenes is important for expanding the design space of nonaqueous multivalent batteries, which often possess higher voltages than their aqueous counterparts. Furthermore, because these nanographenes can be synthesized using a bottom-up approach via alkyne benzannulation, this work paves the way for future battery electrodes that contain other molecularly-precise nanographenes with tailored electrochemical properties.