Synthesis of V2O3@C-CNTs Nanocomposites via In Situ Growth of Carbon Nanotubes from V-MOF for Enhanced Lithium-Sulfur Battery Separators

Abstract

Lithium-sulfur (Li-S) batteries are a promising choice for high-energy-density devices. However, the dissolution and shuttle effect of lithium polysulfides (LiPS) hinder their long-term cycle life and capacity retention. To address these issues, we developed an efficient separator modified with V₂O₃@C-CNTs composite, which combines MOF-derived V₂O₃@C with carbon nanotubes (CNTs). The composite material effectively mitigates the shuttle effect and low conductivity issues by combining CNTs' excellent conductivity with V₂O₃@C's efficient chemical adsorption and catalytic conversion of LiPS. Batteries using the modified separator achieved an initial discharge capacity of 1288.4 mAh g^-1 at 0.5 C, retaining 55.5% of the initial value after 500 cycles. Even with a high sulfur-loaded cathode (5 mg cm^-1), the battery exhibited a capacity retention of approximately 65.4% after 300 cycles at 0.1 C, demonstrating its excellent specific capacity performance.