Uniform small-sized MoS2 from novel solution-based microwave-assisted method with exceptional reversible lithium storage properties

Abstract

Currently, MoS₂ is being investigated as a lithium-ion battery (LIB) anode material because of its high theoretical capacity. However, its significantly low electrochemical activity and cyclic stability limit its utilization. Nevertheless, small-sized MoS₂ possibly overcomes these issues. Herein, small-sized MoS₂ with uniform particle sizes of about 20–30 nm was prepared via a novel solution-based microwave-assisted precursor pyrolysis method. The resultant MW-MoS₂ sample has a high surface area of 96.9 m² g⁻¹ and large pore volume (0.38 cm³ g⁻¹) with pore size distribution mainly in the meso/macropore scale, which are beneficial for electrolyte storage and low charge carrier conductive resistances. The large pore surface area and volume of the small-sized MoS₂ can also ease the volume expansion during the charging and discharging process. As an LIB anode, the MW-MoS₂ material exhibits an amazingly large specific capacity of 1355 mA h g⁻¹ at a low current density of 0.5 A g⁻¹. At a high current density of 10 A g⁻¹, a specific capacity of 435 mA h g⁻¹ is obtained, demonstrating its excellent rate capability. Furthermore, a large discharge capacity of 544 mA h g⁻¹ is maintained after 500 cycles at 5 A g⁻¹, indicating its fascinatingly high cyclic stability.