Porous Biredox Poly(Imine–Anthraquinone) Nanorods Enable Reversible Multielectron Reactions for Symmetric All-Organic Batteries

The structural diversity and sustainability of organic electrode materials make them highly appealing for symmetric all-organic batteries (SAOBs). However, achieving high-performance organic materials with a synergistic effect that involves abundant active centers, strong intermolecular interactions, and a high affinity for sodium ions remains challenging. Herein, we report the development of porous poly(imine–anthraquinone) nanorods (PIAN). The PIAN framework contains abundant C═O and C═N functional groups with distinct redox plateaus, which both serve as cathodic and anodic active centers, respectively, ensuring a high capacity and potential in SAOBs. The conjugated PIAN exhibits a high reversible capacity of 393 mA h g–1 and stable long-term cycling performance (retaining 90 mA h g–1 after 5,000 cycles at 10 A g–1), as confirmed by in situ and ex situ measurements. Furthermore, density functional theory (DFT) calculations reveal that the PIAN electrode possesses rapid Na+ ion diffusion kinetics and follows a two-step multisodium ion storage mechanism. The PIAN-based SAOBs achieve a high capacity of 178 mA h g–1 and retain 79.6% of their initial capacity at 1 A g–1 after 500 cycles. This work introduces a redox-active polymeric electrode material and is expected to inspire further research on organic materials with superior electrochemical performance for practical applications.