Phenothiazine Dimer as Efficient and Recyclable p-Type Organic Positive Electrode Material for Anion-Ion and Dual-Ion Batteries

This article presents the electrochemical properties of a series of phenothiazine and phenoxazine dimers, by involving an aromatic central core, efficiently synthesized in a single step through a Buckwald–Hartwig coupling reaction. A synergistic approach combining experimental and quantum chemical studies was used in view of providing a thorough characterization of their capabilities as electrodes in the context of electrochemical energy storage applications. A detailed study of the electrochemical activity was then conducted with the aim of optimizing performance, i.e., achieving a specific capacity of around 100 mAh.g−1, close to the theoretical values at a potential of 3.6 V relative to Li metal. The dimerization strategy also emerged as an interesting methodology, since it gives rise to molecular materials having specific solubility properties. This finding opens up the possibility of recovering the active material from the electrode at the end of its life, thus paving the way for improved organic electrodes and batteries, especially with respect to their recyclable character.