▎ 摘　　要

Bimetallic selenides are expected to be ideal anode materials for sodium ion batteries (SIBs). However, some problems still need to be solved, such as volume expansion and sluggish redox kinetics of Na ion. This work successfully designed and synthesized a composite of heterostructured SnSe2-CoSe2 microspheres embedded in reduction graphene oxide network (designated as rGO/SnSe2-CoSe2) via one-step hydrothermal and followed annealing selenization process. The micro-nano hierarchical structure and reduction graphene oxide network can accelerate the Na+ transport kinetics and relieve the volume change, thereby promoting the electrochemical performance of SIBs. Furthermore, the weak metal-selenide bonds and heterostructure of the bimetallic boundary can provide numerous active sites. As respect, the composite exhibits a high discharge capacity, enhanced rate capability, and superior cycling performance with a reversible capacity of 395 mAh g(-1) after 600 cycles at 1 A g(-1). These results reveal that this composite will be enormous potentiality in building efficient SIBs.