Sulfur nanodots as MoS2 antiblocking agent for stable sodium ion battery anodes

Abstract

MoS₂ possessing a layered structure with d-space around 0.62 nm is a promising anode material for sodium ion batteries (SIBs), presenting an attractively high theoretical capacity. However, poor cycle stability due to stacking is one of its main challenges. In this work, sulfur nanodots are employed as an efficient antiblocking agent of MoS₂ sheets (S/MoS₂). The S/MoS₂ nanoarchitectures, constructed using few-layered MoS₂ with deposited sulfur nanodots (∼10 nm), are facilely synthesized in a horizontal tube furnace with two temperature-controlled zones. Employed as SIB anode material, the S/MoS₂ architectures deliver a high reversible capacity of 497.6 mA h g⁻¹ at 100 mA g⁻¹, remaining at 413.2 mA h g⁻¹ over 100 cycles. Moreover, the architectures exhibit a capacity of 358.8 mA h g⁻¹ at a higher current density of 500 mA g⁻¹ with excellent cycling stability, surviving 300 full charge/discharge cycles with a retention of 83.8%