1. mAh�g -1 at 100, 300, 500 and 1000 mA�g -1 , respectively. Notably, the specific capacity of SnSe/r-GO can reach to 701.1 mAh�g -1 when the current density is returned to 300 mA�g -1 . CV profiles of SnSe/r-GO was shown in Fig. 3d. The reduction peaks at ~2.0, ~0.89 and ~0.38 V can be assigned to the insertion, conversion and alloying reaction of SnSe, and the oxidation peaks at ~0.57, ~1.3 and ~2.2 V corresponds to the reverse reaction;EIS in Fig. 3f and Fig