Interface-Defect Coupling Modulation in CuCo₂O₄/CuO Heterostructures for Enhanced Lithium Storage Performance

Area of Science:

• Materials Science
• Electrochemistry
• Nanotechnology

Background:

• Developing high-performance anode materials is crucial for advancing lithium-ion battery technology.
• Transition metal oxides offer potential but often face challenges with rate capability and capacity retention.
• Optimizing material structure and electronic properties is key to overcoming these limitations.

Purpose of the Study:

• To fabricate CuCo2O4/CuO composite materials on nickel foam with enhanced oxygen vacancy concentration.
• To investigate the synergistic effects of heterojunction interface engineering and oxygen vacancy regulation on electrochemical performance.
• To provide experimental and theoretical insights for designing advanced anode materials for lithium-ion batteries.

Main Methods:

• Hydrothermal-calcination synergistic approach for material synthesis.
• Fabrication of CuCo2O4/CuO on nickel foam substrates.
• Electrochemical testing to evaluate capacity, rate performance, and cycling stability.
• Density Functional Theory (DFT) calculations to analyze electronic structure and ion diffusion.

Main Results:

• The synthesized CuCo2O4/CuO materials exhibit stacked cluster structures with abundant oxygen vacancies.
• Enhanced carrier enrichment and built-in electric field at the interface reduced charge transfer resistance.
• Significantly improved Li+ adsorption and diffusion efficiency, leading to superior rate performance.
• High reversible capacity of 1170 mAh g-1 after 200 cycles at 0.1 A g-1.
• DFT calculations confirmed reduced bandgap and Li+ diffusion barrier (0.69 eV).

Conclusions:

• The synergistic strategy effectively enhances both high capacity and fast kinetics of transition metal oxide anodes.
• Oxygen vacancy engineering and heterojunction interface design are critical for optimizing anode material performance.
• The developed CuCo2O4/CuO material shows great promise for next-generation lithium-ion batteries.