Interface-Engineered Graphene/Copper Pyrovanadate Cathodes with V-O-C Bonds for Zinc-Ion Storage

Area of Science:

• Materials Science
• Electrochemistry
• Nanotechnology

Background:

• Vanadium-based oxides suffer from poor electronic conductivity and structural instability, hindering their use in zinc-ion batteries.
• Efficient charge transport and structural integrity are crucial for high-performance battery cathodes.

Purpose of the Study:

• To synthesize a graphene-modified copper pyrovanadate (CVOHG) composite for improved zinc-ion storage.
• To investigate the role of graphene in enhancing the electrochemical performance of copper pyrovanadate.

Main Methods:

• One-step hydrothermal synthesis of graphene-modified copper pyrovanadate (CVOHG).
• Characterization of material morphology, structure, and interfacial properties.
• Electrochemical testing of CVOHG as a cathode material for zinc-ion batteries.

Main Results:

• Graphene modification improved nanosheet morphology and created V-O-C interfacial bonds.
• A continuous electron transport network was established, enhancing charge transfer and Zn²⁺ diffusion.
• CVOHG exhibited a 2.5x higher reversible capacity than pristine CVOH, with improved cycling stability (148 mAh g^-1 at 200 mA g^-1 after 200 cycles) and reduced charge-transfer resistance.

Conclusions:

• Interfacial engineering via graphene modification is an effective strategy for designing high-performance metal oxide/carbon composites.
• CVOHG demonstrates significant potential as an advanced cathode material for zinc-ion batteries.
• The study provides valuable insights for developing next-generation energy storage solutions.