Defect engineering on V₂O₃ cathode for long-cycling aqueous zinc metal batteries

Area of Science:

• Materials Science
• Electrochemistry
• Solid-State Chemistry

Background:

• Defect engineering is a key strategy for enhancing electrode material stability in batteries.
• Quantifying defect impacts on electrochemical performance remains challenging.

Purpose of the Study:

• To quantify vanadium-defective clusters in V2O3.
• To evaluate the electrochemical performance of defective V2O3 as a cathode material in aqueous Zn coin cells.

Main Methods:

• Neutron and X-ray powder diffraction
• Positron annihilation lifetime spectroscopy
• Synchrotron-based X-ray analysis
• Density functional theory calculations

Main Results:

• Quantified vanadium-defective clusters up to 5.7% in the V2O3 lattice.
• Achieved 81% capacity retention after 30,000 cycles at 5 A g-1 in aqueous Zn coin cells.
• Identified defect clusters as favorable sites for reversible Zn-ion storage.

Conclusions:

• Vanadium-defective V2O3 demonstrates excellent cycling stability for aqueous Zn batteries.
• Defect clusters facilitate Zn-ion storage by reducing electrostatic interactions.