Facile preparation of robust porous MoS2/C nanosheet networks as anode material for sodium ion batteries

Developing advanced MoS2 anode material for sodium ion battery is still a big challenge since it is hindered by poor cycling stability and rate capability owing to huge volume variation during charge/discharge processes and low conductivity. In this work, three-dimensional porous networks consisting of several-layered MoS2/C nanosheets are synthesized via a facile freeze-drying approach using NaCl as template. MoS2/C nanosheet networks demonstrate a high reversible capacity of 389 mAh g−1 and maintain 370 mAh g−1 after 100 cycles at 100 mA g−1, indicating excellent cycling stability. Good rate properties are also achieved with reversible capacities of 292, 256, 223, 174 mAh g−1 at 1, 2, 4, 6 A g−1, respectively. The excellent electrochemical performance can be ascribed to the unique three-dimensional networks consisting of few-layered MoS2 nanosheets, which facilitates sodium ion diffusion via near-surface reaction. Moreover, the robust three-dimensional carbon matrix can not only provide a conductive network, but also buffer the strain and maintain the electrode integrity during repeated sodiation/desodiation process. This strategy presents a new path for fabricating low-cost and high-yield three-dimensional metal sulfide (phosphide)/carbon composites for applications in energy-related fields and beyond.