Rationally Integrating 2D Confinement and High Sodiophilicity toward SnO₂ /Ti₃ C₂ T_x Composites for High-Performance...

Area of Science:

• Materials Science
• Electrochemistry
• Energy Storage

Background:

• Metallic sodium (Na) is a promising anode material for sodium metal batteries (SMBs) due to its high theoretical specific capacity, low electrode potential, and abundant resources.
• However, practical application of sodium metal anodes (SMAs) is hindered by sodium vaporization during plating/stripping and uncontrolled sodium dendrite growth.

Purpose of the Study:

• To address the challenges of sodium vaporization and dendrite growth in SMAs.
• To develop a novel composite material for stable and efficient sodium metal anodes.

Main Methods:

• Fabrication of a SnO2/Ti3C2Tx composite with in-situ dispersed sodiophilic SnO2 nanoparticles on 2D Ti3C2Tx.
• Characterization of the composite anode's morphology, electrochemical performance, and stability in half and full cells.

Main Results:

• The SnO2/Ti3C2Tx composite anode demonstrated controlled sodium vaporization and dendrite suppression.
• Achieved smooth and homogeneous anode morphology after cycling, stable Coulombic efficiency in half cells, and long cycle life in symmetric cells.
• Full cells using Na0.6MnO2 cathodes exhibited excellent rate and cycling performance.

Conclusions:

• The SnO2/Ti3C2Tx composite effectively utilizes acceptor sites and confinement effects to enhance SMA performance.
• This composite provides a new design strategy for developing high-performance sodium metal batteries.