Superhydrophilic All‐pH‐Adaptable Redox Conjugated Porous Polymers as Universal and Ultrarobust Ion Hosts for Diverse Energy Storage with Chemical Self‐Chargeability

Abstract

AbstractHerein, a new fibrous conjugated microporous polymer bearing phenazine species (PNZ‐CMP) is reported as a universal and ultrastable electrode to host various mono‐ and multi‐valent charge carriers for diverse aqueous rechargeable cells combining rapid kinetics, ultralong lifespan, and chemical rechargeability. The porous cross‐linked structure, interconnected donor‐acceptor network, and readily accessible active sites endow PNZ‐CMP with highly‐reversible redox activity, superhydrophilicity, facile electron transport, high ion diffusion coefficient, and all‐pH‐adaptability (−1 to 15) in aqueous electrolytes. Thus, adopting PNZ‐CMP electrodes enables good compatibility with H+/Li+/Na+/K+/Zn2+/Al3+ ions and fast surface‐controlled redox reactions for diverse aqueous battery chemistry. Multiple PNZ‐CMP‐based full cells show superior electrochemical performance especially ultralong lifespan, e.g., ≈84% capacity retention over 200 days for K+, ≈100% over 127 days for Zn2+, and ≈76% over 47 days for anion‐coordinated Al ions, surpassing small molecule counterparts and most previously‐reported corresponding systems. The spontaneous redox chemistry of reduced phenazine species with O2 is first explored to render PNZ‐CMP with repeatable chemical self‐chargeability in four electrolytes. Especially in 0.05 m H2SO4, an accumulative discharge capacity up to 48505 mAh g−1 is achieved via facile self‐charging, which can originate from the “reactive antiaromaticity to stable aromaticity” conversion of the redox moieties as revealed by theoretical studies.