Three-dimensional (3D) flower-like MoSe2/N-doped carbon composite as a long-life and high-rate anode material for sodium-ion batteries

Abstract Molybdenum-based composites have attracted tremendous attention as active material fillers for sodium ion batteries (SIBs) due to their high capacity. Herein, three-dimensional (3D) Flower-like MoSe2/nitrogen-doped carbon (MoSe2/CN) composite was successfully prepared through a facile hydrothermal route and followed by annealing treatment. When tested as anode for SIBs, the as-prepared MoSe2/CN composite shows outstanding electrochemical performance, including a good cycling stability (328.7 mA h g−1 after 500 cycles at 1.0 A g−1) and high rate capability (523.6, 407.4, 370, 347, 326, 310.2 and 300.1 mA h g−1 at 0.1, 0.5, 1.0, 2.0, 3.0, 4.0 and 5.0 A g−1, respectively). The excellent Na-ion storage performance of the MoSe2/CN composite can be ascribed to the synergistic coupling effect between MoSe2 and nitrogen-doped carbon, which could enhance kinetically facile and cycling stability during the charge and discharge process. Furthermore, in situ XRD results suggest that the capacity fading during cycling is caused by structural instability resulting from the conversion reaction.