Fabrication of Bi2Se3/Mo3Se4 composite for efficient sodium storage

In this work, the Bi 2 Se 3 /Mo 3 Se 4 composite is obtained through electrochemical activation of Bi 2 Se 3 /MoSe 2 composite, which has been synthesized by an ordinary hydrothermal reaction closely followed by selenization process. The Bi 2 Se 3 /Mo 3 Se 4 composite appears good electrochemical property as the negative electrode material for sodium ion batteries (the stable reversible capacity is 409 (346) mAh g −1 at 100 (1000) mA g −1 ). The outstanding electrochemical property can be attributed to the unique Bi 2 Se 3 /Mo 3 Se 4 composite architecture, in which Bi 2 Se 3 is responsible for offering a high capacity, and Mo 3 Se 4 is responsible for improving electrochemcial stability. Moreover, the small particle sizes for Bi 2 Se 3 /Mo 3 Se 4 resulting from the amorphous to crystalline transitions during cycling is also the cause of the increased stability of the electrode. The design of the Bi 2 Se 3 /Mo 3 Se 4 composite provides a potential tactics to construct other metal selenides composites for sodium-ion battery anode. • Bi 2 Se 3 /Mo 3 Se 4 composite was synthesized by convenient strategy. • Bi 2 Se 3 /Mo 3 Se 4 composite exhibits excellent cycling performance for SIBs anode. • Bi 2 Se 3 /Mo 3 Se 4 composite shows good rate capability for SIBs anode.