Realizing Dual-Mode Zinc-Ion Storage of Generic Vanadium-Based Cathodes via Organic Molecule Intercalation

Intercalation engineering is a promising strategy to promote zinc-ion storage of layered cathodes; however, is impeded by the complex fabrication routes and inert electrochemical behaviors of intercalators. Herein, an organic imidazole intercalation strategy is proposed, where V2O5and NH4V3O8(NVO) model materials are adopted to verify the feasibility of the imidazole intercalator in improving the zinc storage capabilities of vanadium-based cathodes. The intercalated imidazole molecules could not only expand interlayer spacing and strengthen structural stability by serving as extra “pillars” but also provide extra coordination sites for zinc storage via the coordination reaction between Zn2+and the C═N group. This gives rise to a dual-mode ion storage mechanism and favorable electrochemical performances. As a result, imidazole-intercalated V2O5delivers a capacity of 179.9 mAh g–1after 5000 cycles at 20 A g–1, while the imidazole-intercalated NVO harvests a high capacity output of 170.2 mAh g–1after 700 cycles at 2 A g–1. This work is anticipated to boost the application potentials of vanadium-based cathodes in aqueous zinc-ion batteries.