Mo2C-engineered coconut fiber-derived porous carbon with synergistic adsorption-catalysis interface for lithium-sulfur batteries

Abstract

To enhance sulfur redox kinetics and cycling durability in Li−S batteries, a Mo 2 C-anchored alkali-activated coconut fiber carbon framework (Mo 2 C/A-CFC) was constructed as an advanced sulfur host. The three-dimensional porous network provides plentiful accessible surface sites and continuous pathways for electron/ion migration, thereby ensuring efficient sulfur confinement and accommodating the substantial volume variation during charge–discharge processes. Furthermore, the incorporation of uniformly distributed Mo 2 C nanoparticles simultaneously improves charge transport, strengthens polysulfide anchoring, and promotes sulfur redox kinetics, thereby effectively suppressing shuttle-induced capacity decay. Benefiting from these synergistic features, the Mo 2 C/A-CFC/S cathode exhibits an initial capacity of 1072 mAh g −1 at 0.2C and retains 72.7% of its capacity after 200 cycles. Under reduced-electrolyte conditions with a sulfur loading of 3.6 mg cm −2 and an E/S ratio of 12.72 μL mg −1 , it maintains a reversible capacity of 622 mAh g −1 after 100 cycles. This work presents a scalable strategy for engineering catalytic sulfur hosts and provides insights into the development of high-performance Li−S batteries.