Ferroelectric-Polarization-Driven Structural Engineering of Bi₃Nb₁₇O₄₇ Anodes for High-Performance Lithium-Ion...

Area of Science:

• Materials Science
• Electrochemistry
• Solid-State Chemistry

Background:

• Metal-ion batteries require optimized electrode materials for higher capacity and stability.
• Current strategies like defect engineering and doping have limitations.
• Tungsten bronze (TTB)-type Bi3Nb17O47 has a theoretical capacity but limited Li+ storage.

Purpose of the Study:

• To explore a ferroelectric-polarization strategy for modulating Bi3Nb17O47 structure.
• To enhance Li+ storage capacity and cycling stability of the anode material.

Main Methods:

• Utilized ferroelectric polarization to engineer the crystal structure of Bi3Nb17O47.
• Analyzed structural changes, including Nb5+ displacements and O2- contraction.
• Evaluated electrochemical performance across various current densities (0.1-10 C).

Main Results:

• Polarization enlarged Li+ storage cavities by ~8%.
• Reversible capacities increased by 36%-55% at different current densities.
• Enhanced cycling stability with 84.9% capacity retention after 1000 cycles at 5 C.

Conclusions:

• Ferroelectric-polarization is a viable strategy for structural engineering in energy storage materials.
• This approach significantly improves the electrochemical performance of TTB-type anodes.
• Pioneers electric-field-driven modification for high-performance metal-ion batteries.