WSe₂ Flakelets on N-Doped Graphene for Accelerating Polysulfide Redox and Regulating Li Plating

Area of Science:

• Materials Science
• Electrochemistry
• Energy Storage

Background:

• Lithium-sulfur (Li-S) batteries offer high theoretical energy density but face challenges.
• The lithium polysulfide (LiPSs) shuttling effect and lithium dendrite growth hinder practical application.

Purpose of the Study:

• To develop a dual-functional host material for both the sulfur cathode and lithium anode.
• To address LiPSs shuttling and Li dendrite growth in Li-S batteries.

Main Methods:

• Designed WSe2 flakelets immobilized on N-doped graphene (WSe2/NG).
• Investigated WSe2/NG as a host for LiPSs and for regulating Li plating/stripping.
• Assembled and tested Li-S full batteries with WSe2/NG.

Main Results:

• WSe2/NG demonstrated strong interaction with LiPSs, acting as a redox accelerator.
• WSe2/NG exhibited excellent lithiophilic features, promoting uniform Li plating/stripping.
• Li-S full batteries showed remarkable rate performance and stable cycling stability at high sulfur loading (10.5 mg cm⁻²).

Conclusions:

• The WSe2/NG dual-functional host effectively mitigates key limitations in Li-S batteries.
• This material design offers a promising strategy for advancing high-performance Li-S battery technology.