Preparation of Nitrogen-Doped Foam Carbon Coupled with Manganese Sulfide Particles as a Composite Cathode and Optimization of Lithium-Sulfur Battery Performance.

Abstract

Lithium-sulfur batteries (LSBs) are ideal for next-generation energy storage systems due to their high energy density (2600 Wh kg^-1) but face challenges like the polysulfide shuttle effect, slow redox kinetics, and low sulfur utilization. This study constructs MnS-PNC composite materials by uniformly growing MnS nanoparticles on N-doped carbon nets (PNC) via a hydrothermal method, using them as cathode sulfur host materials for LSBs. The 3D network structure of the carbon material provides sufficient space for active sulfur loading, and N-doping enhances the carbon material's polarity to strengthen interaction with lithium polysulfides. MnS nanoparticles on the carbon net act as catalytic active centers and chemical anchoring sites. Their synergy with PNC effectively alleviates the shuttle effect and enhances active material utilization. Electrochemical tests show: at 1 mg cm^-2 loading, initial discharge capacity reaches 1079.1 mAh g^-1 at 0.2 C; after 500 cycles at 1 C, it maintains 575.5 mAh g^-1 with an average decay rate of 0.056% per cycle, indicating S@MnS-PNC is a promising LSB cathode host material.