Dual-metallic site regulation boosts charge storage in zinc-ion hybrid supercapacitors

Zinc-ion hybrid supercapacitors (ZIHCs) are promising next-generation energy storage devices owing to their high safety and low cost. However, conventional carbon-based cathodes still suffer from limited capacity and energy density.

In this work, we developed carbon nanofiber cathodes with a hierarchical porous structure and a unique ZnFeN₆ coordination design via electrospinning and controllable carbonization. The introduction of Fe regulates the local electronic environment of Zn atoms, enhancing ion adsorption and charge transfer. Meanwhile, the large surface area (879 m² g^-1) and interconnected pore network facilitate ion transport. As a result, the ZnFe/PCNFs delivers a high capacity of 213 mAh g^-1 at 0.1 A g^-1, maintains 128 mAh g^-1 at 10 A g^-1, and retains 88.6% of their capacity after 20000 cycles. 

This study demonstrates an effective bimetallic design approach that provides valuable guidance for developing safer, longer-lasting, and higher-energy aqueous energy storage devices. The work titled “Dual-Metallic Site Regulation Boosts Charge Storage in Zinc-Ion Hybrid Supercapacitors” was published in Advanced Powder Materials (published on Oct. 22, 2025).