Promoting Electrochemical Reactions with Dual-Atom Catalysts for High-Rate Lithium-Sulfur Batteries

Area of Science:

• Materials Science
• Electrochemistry
• Energy Storage

Background:

• Sulfur cathodes are promising for high-energy-density, cost-effective, and sustainable energy storage.
• Sluggish sulfur redox reactions (SRRs) limit the practical application of sulfur cathodes in lithium-sulfur batteries (LSBs).

Purpose of the Study:

• To develop a scalable and cost-effective strategy for synthesizing catalysts to activate SRRs in LSBs.
• To investigate the potential of 3d transition metal-bismuth (TM-Bi) atomic pairs anchored on carbon nitride (CN) for enhancing LSB performance.

Main Methods:

• Synthesis of TM-Bi/CN catalysts.
• Electrochemical analysis, including rate performance and stability testing.
• Density functional theory (DFT) calculations and operando spectroscopy.

Main Results:

• Ni-Bi/CN and Co-Bi/CN catalysts were identified as highly effective in improving LSB rate performance.
• These catalysts promote direct electrochemical transitions and rapid Li2S nucleation over competing chemical pathways.
• Catalyst-enhanced LSBs demonstrated high charge-discharge rates, minimized active material loss, and enhanced stability.

Conclusions:

• Accelerating electrochemical processes, particularly Li2S nucleation, is crucial for minimizing sulfur loss and achieving high-rate performance in LSBs.
• TM-Bi atomic pairs on CN effectively activate SRRs by modulating electronic structures and promoting efficient charge transfer.
• The findings provide insights for designing advanced catalysts for LSBs and other electrocatalytic applications.