Exploiting deep sulfur conversion by tandem catalysis for all-solid-state lithium-sulfur batteries

Area of Science:

• Materials Science
• Electrochemistry
• Catalysis

Background:

• All-solid-state lithium-sulfur batteries (ASSLSBs) offer high energy density and safety.
• Incomplete sulfur conversion limits the full capacity of ASSLSBs.

Purpose of the Study:

• To achieve deep conversion of S₈ to Li₂S via Li₂S₂ using tandem catalysis.
• To enhance the capacity and performance of ASSLSBs.

Main Methods:

• Utilizing cobalt single-atom catalysts (Co SACs) on a MXene substrate for tandem catalysis.
• Investigating the stepwise reduction of S₈ to Li₂S through the Li₂S₂ intermediate.

Main Results:

• Demonstrated stepwise S₈ reduction to Li₂S via Li₂S₂ using Co@MXene.
• Co SACs broke S-S bonds, and MXene facilitated Li⁺ diffusion, lowering energy barriers.
• Achieved a high capacity of 1329 mAh g⁻¹ after 2000 cycles at 2.8 mA cm⁻² at room temperature.

Conclusions:

• Tandem catalysis effectively tailors the sulfur conversion pathway in ASSLSBs.
• This strategy unlocks deep sulfur conversion for high-performance ASSLSBs.