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

Area of Science:

• Materials Science
• Electrochemistry
• Energy Storage

Background:

• Intercalation engineering is key for layered cathode materials in zinc-ion batteries.
• Current methods face challenges due to complex fabrication and poor intercalator activity.

Purpose of the Study:

• To introduce an organic imidazole intercalation strategy for vanadium-based cathodes.
• To enhance zinc-ion storage capabilities and electrochemical performance.

Main Methods:

• Imidazole molecules were intercalated into V2O5 and NH4V3O8 (NVO) structures.
• Electrochemical performance was evaluated for zinc-ion storage.

Main Results:

• Imidazole intercalation expanded interlayer spacing and enhanced structural stability.
• A dual-mode ion storage mechanism was observed, involving expanded spacing and coordination sites.
• Imidazole-intercalated V2O5 achieved 179.9 mAh g⁻¹ after 5000 cycles at 20 A g⁻¹.
• Imidazole-intercalated NVO achieved 170.2 mAh g⁻¹ after 700 cycles at 2 A g⁻¹.

Conclusions:

• Organic imidazole intercalation is a viable strategy to improve vanadium-based cathodes for aqueous zinc-ion batteries.
• The dual-mode ion storage mechanism significantly enhances capacity and cycling stability.