Effect of phosphorus-modified TiN mesoporous MXene interlayer as a polysulfide electrocatalyst in Li-S battery

Abstract

The research on lithium-sulfur batteries (LSBs) addresses the challenges of sulfur's insulating properties and the 'shuttle effect' of lithium polysulfides (LiPSs) hindering their commercialization. The introduction of a phosphorous-modified mesoporous Titanium Nitride (TiN) interlayer for the S@MWCNTs cathode demonstrates significant advancements in enhancing conductivity and enabling greater sulfur loading. This modification minimizes the LiPS's 'shuttle effect' through robust chemical bonds with phosphorous loading, leading to superior electrochemical performance. Electrochemical analyses reveal that the phosphorous-modified TiN offers a greater number of active sites for catalyzing redox reactions of the sulfur cathode. The phosphorous-modified mesoporous titanium nitride (P-TiN) interlayer exhibits impressive electrochemical performance, delivering a capacity of 358 mAh g−1 after 320 cycles at 0.1 C and demonstrating high-rate performance of 380 mAh g−1 at 1 C.

Keywords

• Lithium sulfur battery
• TiN mesoporous
• Electrocatalyst
• Polysulfides
• Mxene