Constructing Heterogeneous Structure in Metal-Organic Framework-Derived Hierarchical Sulfur Hosts for Capturing...

Area of Science:

• Materials Science
• Electrochemistry
• Energy Storage

Background:

• Lithium-sulfur batteries (LSBs) face challenges from polysulfide (LiPS) shuttle, limiting sulfur utilization and battery life.
• Designing effective hosts with catalytic properties is crucial for mitigating LiPS shuttle and improving LSB performance.

Purpose of the Study:

• To develop a hierarchical sulfur host incorporating a Bi/Bi2O3 heterostructure for enhanced lithium-sulfur battery performance.
• To investigate the mitigation of LiPS shuttle effects and promotion of redox kinetics using the novel host material.

Main Methods:

• Fabrication of a metal-organic framework (MOF)-derived hierarchical carbon host.
• Integration of a dual-functional Bi/Bi2O3 heterostructure within the host structure.
• Electrochemical characterization of the fabricated lithium-sulfur batteries.

Main Results:

• The Bi/Bi2O3 heterostructure effectively adsorbs and catalytically converts LiPSs, suppressing the shuttle effect.
• The developed LSBs demonstrate a high discharge capacity of 740.8 mAh g⁻¹ over 1000 cycles at 1 C with a low decay rate of 0.022% per cycle.
• High areal capacity (6.6 mAh cm⁻²) was achieved with a sulfur loading of 8.1 mg cm⁻², and promising performance in pouch cells.

Conclusions:

• The Bi/Bi2O3 heterostructure within the MOF-derived host is a promising strategy for advanced lithium-sulfur batteries.
• This approach significantly improves sulfur utilization, cycle stability, and overall battery performance.
• The study highlights the potential of tailored heterostructures for next-generation energy storage devices.