Polymer-water interaction's importance in the redox kinetics and mechanism of TEMPO-substituted radical polymers

TEMPO-substituted radical polymers represent a kind of high voltage and fast-charging active material for metal-free, aqueous organic batteries. However, the relationship between the structure and performance of TEMPO-substituted radical polymers remains unclear, and design principles of an electrode-electrolyte system to guide future designs are lacking. In this talk, the relationship between the structure and performance of a series of non-conjugated TEMPO-substituted radical polymers are elucidated in a water-based electrolyte containing organic salt. A series of these polymers with varying hydrophilicities are explored. It is shown that the polymer-water interactions influence the redox kinetics of the polymers. Moreover, the coupled mass and charge transfer behavior of these TEMPO-substituted radical polymers are monitored using electrochemical quartz crystal microbalance with dissipation monitoring, indicating a varying hydration degree of the transferred species during the anion doping/dedoping reaction. These results reveal the important role of designing the polymer structure and adjusting polymer-water interactions in driving the overall performance.