Fully-conjugated polyimidazole nanoparticles as active material in bi-odegradable electrodes for organic batteries

Abstract

Conjugated polymers are promising active materials for batteries. Batteries not only need to have high energy density but should also combine safe handling with recyclability or biodegradability after reaching their end-of-life. Here, we develop π-conjugated polyimidazole particles, which we prepare using atom economic direct arylation adapted to a dis-persion polymerization protocol. The synthesis yields polyimidazole nanoparticles with tunable size and narrow dispersi-ty. In addition, the degree of crosslinking of the polymer particles can be controlled. We demonstrate that the polyimid-azole nanoparticles can be processed together with carbon black and biodegradable carboxymethyl cellulose binder as active material for organic battery electrodes. Electrochemical characterization shows that a higher degree of crosslink-ing significantly improves the electrochemical processes and leads to clearer oxidation and reduction signals from the polymer. Polyimidazole as part of the composite electrode shows complete degradation by exposure to composting bac-teria over the course of 72 h.