Bipolar Dihydrotetraazapentacene for Aqueous Zinc-Organic Batteries via Proton/Anion Co-storage

Bipolar organic electrode materials featuring n-p fused architectures, which enable precise integration of diverse nitrogen species within π-conjugated frameworks, present a strategic pathway toward high-performance aqueous zinc-organic batteries. In this study, a bipolar-redox dihydro-5,7,12,14-tetraazapentacene (DHTAP) cathode is reported that incorporates electron-donating (p-type) piperazine subunits and electron-accepting (n-type) pyrazine moieties into a pentacene-based carbon skeleton. The synergistic nitrogen-doping strategy effectively modulates the electronic structure and enhances the stability of redox intermediates. DHTAP delivers a high specific capacity of 264 mAh g^-1 at 0.1 A g^-1, with concurrent demonstration of exceptional rate capability (80% capacity retention at 20C) and stable long-cycle performance (10,000 cycles at 4.39 A g^-1). Comprehensive mechanistic studies reveal that protons preferentially coordinate with pyrazine units at low potential, while anions bind to piperazine units at higher potential. This dual-ion storage mechanism facilitates electrochemical reactions with a low energy barrier, providing new insights into the design of advanced organic electrodes through multi-electron transfer processes.