Co-regulated proton confinement and uptake mechanisms for ultra-fast and robust aqueous Zn-organic batteries

Central to the progression of aqueous zinc-organic batteries (AZOBs) is the exploration of durable organic hosts capable of fast ion diffusion within electrolytes and electrode interiors. Compared with Zn²⁺ insertion, developing proton-storage organic cathodes along with optimizing charge transport across the cathode-electrolyte interface remains difficult but critical for improved AZOBs. Herein, quinone-based molecules, particularly Menadione (2-methyl,1–4, naphthoquinone), were uniformly separated onto negative-charged porous carbon (PC) particles as the organic cathode. Due to the negative-charged −COOH and − OH groups, H⁺ movement is confined merely inside the cathode to eliminating interfacial charge transport barriers for fast-charging and robust PC-supported Menadione cathode based on reversible C=O/C-OH reaction. As a result, Zn//Menadione battery exhibits an ultra-high capacity (313 mAh g⁻¹), superb rate capability, and ultra-long lifespan over 20,000 cycles at 30 A g⁻¹, superior to most reported organic cathodes. This work provides novel insights into exploring proton-insertion chemistry within small organic cathodes for advanced Zn batteries.