1 T-rich MoS2/nitrogen-doped graphene composites: Advanced anode materials to improve the performance of lithium-ion batteries

Abstract

Molybdenum disulfide (MoS₂) is recognized as a highly promising anode material for lithium-ion batteries (LIBs) due to its two-dimensional layered structure and substantial theoretical specific capacity. The 1 T phase of MoS₂, which significantly influences electrochemical performance, offers markedly higher conductivity. However, the metastable nature of 1 T-MoS₂ complicates its direct synthesis under standard conditions, making it susceptible to transformation into the less conductive 2H phase through restacking, which in turn degrades its electrochemical properties. This study employed glucose molecules to facilitate the in situ growth of 1 T-rich MoS₂ on N-doped graphene via a simple and efficient one-step hydrothermal method. The glucose molecules uniformly insert themselves into the MoS₂ interlayers, effectively expanding the interlayer spacing while preserving structural stability and enhancing reaction kinetics. Additionally, the novel interface between carbon-inserted MoS₂ and N-doped graphene (NG) creates an efficient transport channel for the rapid transfer of electrons and Li⁺ ions from graphene to the MoS₂ plane. Electrochemical characterization reveals that the MoS₂/C@G composite demonstrates excellent bidirectional reaction kinetics and high reversible capacity. Even at a current density of 2 A g⁻¹ after 1000 cycles, the MoS₂/C@G composite retains a capacity of 1022.4 mAh g⁻¹. This work proposes a viable strategy for preparing 1 T-rich MoS₂-based anode materials, highlighting their significant potential for energy storage device applications.