A Robust Metal-Organic Framework Derived Bioinspired Metal-Polyphenol Network Interface for Enhanced Sodium Storage

Area of Science:

• Materials Science
• Electrochemistry
• Nanotechnology

Background:

• Flexible anode materials are essential for next-generation flexible and wearable electronics.
• Current flexible current collectors for sodium-ion batteries (SIBs) exhibit poor interfacial stability and mechanical properties.

Purpose of the Study:

• To develop a novel flexible anode material with enhanced interfacial stability and mechanical properties for SIBs.
• To utilize a bionic metal-phenolic network (MPN) strategy inspired by biomineralization principles for interfacial engineering.

Main Methods:

• A one-step calcination-sulfidation treatment was applied to a metal-organic framework (MOF) precursor on a flexible substrate.
• The MOF precursor was transformed into Fe7S8 nanoparticles anchored on carbonized silk fabric.
• A bionic MPN was formed via coordination between tannic acid and Fe3+ to direct MOF growth and create a carbon interlayer.

Main Results:

• The optimized MSMF-2 composite demonstrated excellent structural integrity after 2000 bending cycles.
• It achieved a specific areal capacity of 1.40 mAh cm-2 after 200 cycles and 97.3% capacity retention after 1000 cycles.
• Stable interfacial passivation and dual intercalation-conversion storage behavior were observed.

Conclusions:

• The bionic MPN strategy effectively integrates MOF-derived active materials for flexible SIB anodes.
• This approach offers a promising solution for developing high-performance flexible energy storage devices.
• The study highlights the potential of biomimetic interfacial regulation in advanced materials design.