▎ 摘　　要

Transition-metal phosphides (TMPs) have emerged as anode materials for lithium-ion batteries owing to their high theoretical capacity and stable cyclability. Moreover, by increasing the content of P in TMPs, their lithium storage performance can be further improved. However, the decreased electrical conductivity caused by continuous increment of the P doping into metal and the large volume change during the lithiation/delithiation process limit the electrical energy storage applications of such materials. The combination of the advantages of graphene and a hollow structure is regarded as an approach to solve these issues. In this work, CoP nanocages wrapped by reduced graphene oxide (CoP@RGO) were fabricated via a template-based method followed by a low-temperature phosphating process. Such a unique structure can not only accommodate the volume change during the lithiation/delithiation process but also improve the electric conductivity of the CoP nanocages. The obtained CoP@RGO nanocages exhibited remarkable stable capacity of 546.6mAhg(-1) at current density of 100mAg(-1) over 500 cycles (or 460.4mAhg(-1) at current density of 500mAg(-1) over 500 cycles).