Carbon-intercalated MoS2 on hollow carbon spheres derived from yeast with Mo–C bonding for enhanced sodium storage

Abstract

Molybdenum disulfide (MoS₂) holds great potential for sodium storage owing to its unique layered structure and high theoretical capacity. However, the low conductivity and large volume expansion hinder its practical applications. Herein, monolayer carbon-intercalated MoS₂ nanosheets anchored on yeast-derived N-doped carbon (mC-MoS₂/YNC) with Mo–C bonding are prepared by a simple hydrothermal method. As a biomass carbon source, yeast provides a hollow sphere template to anchor MoS₂ nanosheets through Mo–C bonding, which alleviates the volume expansion and improves conductivity and structural stability. More importantly, the intercalated monolayer carbon derived from yeast significantly expands the interlayer spacing (1.02 nm) and constructs few-atomic-layer MoS₂, which prevents nanosheets from restacking, provides sufficient sodium storage sites, and enhances Na⁺ diffusion kinetics. Consequently, mC-MoS₂/YNC delivers highly reversible capacity (485.5 mAh g⁻¹ at 0.1 A g⁻¹), excellent rate performance (201.5 mAh g⁻¹ at 10 A g⁻¹), and cycling stability. Moreover, density functional theory calculations reveal strong coupling of Mo–C and intercalated carbon can promote charge transfer, improve Na⁺ adsorption, and enhance electrochemical reaction kinetics. Furthermore, the assembled mC-MoS₂/YNC||NVP/C full cell has excellent sodium storage properties. The strategy of combining biomass carbon template, chemical bonding and interlayer engineering provides a novel perspective for preparing high-performance layered structure anodes.