Robust Solid Electrolyte Interphase Engineered by Catalysis Chemistry Toward Durable Anode-Free Sodium Metal...

Area of Science:

• Materials Science
• Electrochemistry
• Energy Storage

Background:

• Anode-free sodium metal batteries (AFSMBs) offer high energy density for large-scale energy storage.
• Sodium dendrite growth is a major obstacle to the practical application of AFSMBs.
• A robust solid electrolyte interphase (SEI) is crucial for suppressing dendrite formation.

Purpose of the Study:

• To develop a novel strategy for constructing a mechanically robust and ionically conductive SEI layer.
• To investigate the effectiveness of a catalysis chemistry approach in inhibiting sodium dendrite growth.
• To enhance the cycling stability and performance of AFSMBs.

Main Methods:

• Introduced Ruthenium (Ru) catalytic sites onto a copper current collector.
• Constructed an ultra-thin (∼5 nm), NaF-rich, and high-strength (203 MPa) SEI layer via catalysis chemistry.
• Evaluated the performance of Ru-modified Cu//Na asymmetric cells and AFSMBs under various cycling conditions.

Main Results:

• The Ru-modified SEI layer effectively promoted rapid Na⁺ diffusion and inhibited dendrite growth.
• Ru modified-Cu//Na asymmetric cells demonstrated exceptional cycling stability over 2000 hours (1000 cycles).
• AFSMBs with Ru-modified current collectors maintained 98.1% capacity retention after 100 cycles at 0.5 C.

Conclusions:

• Catalysis chemistry is a promising approach for developing advanced sodium metal anodes.
• The engineered SEI layer significantly enhances the safety and performance of AFSMBs.
• This work provides a new perspective for designing efficient SEI layers for battery applications.