Ethylene glycol solvent induced expansion of interplanar spacing and 2H-1T phase transformation of molybdenum disulfide nanocomposites for enhanced lithium storage capability

Molybdenum disulfide (MoS₂), has aroused people's much research interest as an anode candidate for next generation of Li-ion batteries because of special layered structure and high theoretical capacity. However, MoS₂ suffers from a poor cycling stability and an inferior rate capability upon charge/discharge processes. So we have successfully synthesized a more stable expanded nanocomposite with superior electrical conductivity by intercalating moderate amorphous carbon between two adjacent S–Mo–S interlayer via a simple method which exhibits excellent lithium storage performance with high capacity (858.9 mA h g⁻¹ at 1 A g⁻¹ for 1000 cycles), and superior rate capability (518 mA h g⁻¹ at 4 A g⁻¹). This superior electrochemical performance is attributed to the special structure (few layers, 2H phase, expanded interlayer spacing, amorphous carbon between S–Mo–S layers, C–O–Mo bond in the layer), small size and evenly distributed MoS₂ nanosheets. Besides, we study the 2H-1T phase transformation mechanism by controlling the ratio of ethylene glycol to water and O–C[dbnd]O bond plays an important role in promoting 2H-1T phase transformation.