Enhancing Kinetics in Sodium Super Ion Conductor Na₃MnTi(PO₄)₃ through Microbe-Assisted and Structural Optimization

Area of Science:

• Materials Science
• Electrochemistry
• Energy Storage

Background:

• Sodium (Na) super ion conductor (NASICON) structured Na3MnTi(PO4)3 (NMTP) is a promising cathode material for sodium-ion batteries.
• Its practical application is hindered by poor electronic conductivity and slow reaction kinetics.

Purpose of the Study:

• To develop a novel NMTP cathode with enhanced electrochemical performance.
• To improve electronic conductivity and sodium-ion diffusion pathways.

Main Methods:

• Fabrication of a three-dimensional cross-linked porous NMTP architecture using Aspergillus niger (AsN).
• Optimization of NMTP cathode structure by adjusting transition metal Mn/Ti ratios.
• Sintering the AsN@NMTP/C material at 650 °C.

Main Results:

• The AsN@NMTP/C-650 material demonstrated improved electronic conductivity and controlled Na+ diffusion.
• The optimized Na3.4Mn1.2Ti0.8(PO4)3 cathode exhibited excellent electrochemical performance.
• High reversible capacity and capacity retention of 89.3% after 1000 cycles at 2C were achieved.

Conclusions:

• The AsN@NMTP/C composite material effectively enhances the performance of NMTP cathodes.
• Optimizing the Mn/Ti ratio is crucial for achieving superior electrochemical properties in NMTP-based sodium-ion batteries.