Incorporation of Organic Benzoquinone Framework Into rGO via Strong π-π Interaction for High-Performance Aqueous...

Aqueous ammonium-ion batteries (AAIBs) are promising candidates for next-generation energy storage devices. However, organic materials as suitable anodes face severe challenges due to their structural instability and poor conductivity, which hinder the development of AAIBs. Herein, an innovative approach is introduced by incorporating an organic benzoquinone framework, 5,7,11,14-tetraaza-6,13-pentacenequinone (TAPQ), with reduced graphene oxide (rGO) using a solvent exchange method. Benefiting from π-π interaction and electron delocalization, TAPQ/rGO features enhanced cycling stability and ion/electron transportation. Consequently, the composite electrode delivers a reversible capacity of 181.7 mAh g^-1 at 0.5 A g^-1 and achieves an ultrahigh capacity retention of 94.5% over 10 000 cycles at 5 A g^-1, surpassing most reported anodes in AAIBs. Combining density functional theory (DFT) calculation and ex situ electrochemical characterizations, the unique storage mechanism of chelation coordination between NH₄ ⁺ and N, O is revealed. Furthermore, a high-performance NH₄ ⁺-based full cell, assembled with TAPQ/rGO anode and copper hexacyanoferrate (Cu-HCF) cathode, demonstrates long-term cycling stability with 93.95% capacity retention after 500 cycles. This work pioneers the concept of π-π interactions to significantly improve NH₄ ⁺ storage performance, presenting a novel strategy for the advancement of AAIBs research.