Two-dimensional Co(OH)₂/graphene oxide composite as an efficient multifunctional interlayer for high-performance...

Area of Science:

• Materials Science
• Electrochemistry
• Energy Storage

Background:

• Polysulfide shuttling is a major challenge hindering the practical application of lithium-sulfur (Li-S) batteries.
• Developing effective strategies to suppress polysulfide shuttling is crucial for improving Li-S battery performance.

Purpose of the Study:

• To design and fabricate a novel flexible interlayer to mitigate polysulfide shuttling in Li-S batteries.
• To investigate the structural and electrochemical properties of the developed interlayer.

Main Methods:

• A flexible interlayer was synthesized using a simple vacuum filtration technique, combining two-dimensional α-cobalt hydroxide (α-Co(OH)₂) nano-plates and graphene oxide (GO).
• The interlayer was characterized for its layered structure and its ability to physically and chemically trap lithium polysulfides (LiPS).

Main Results:

• The α-Co(OH)₂/GO interlayer effectively formed a physical barrier and demonstrated strong chemical adsorption and catalytic conversion of LiPS.
• Li-S batteries utilizing this interlayer exhibited an initial discharge capacity of 834 mAh g^-1 at 1 C.
• A high capacity retention of 590 mAh g^-1 was achieved after 300 cycles, with a low capacity fading rate of 0.1% per cycle.

Conclusions:

• The developed α-Co(OH)₂/GO interlayer successfully suppressed polysulfide shuttling, significantly improving the cycling stability and capacity retention of Li-S batteries.
• This work presents a feasible and scalable method for preparing multifunctional interlayers for advanced Li-S battery applications.