▎ 摘 要
As one of the most promising anode materials, MnO2 has attracted much attention due to its much higher theoretical capacity. However, the low electrical conductivity and the large specific volume change limit its performance. Herein we synthesize rodlike MnO2/reduced graphene oxide (RGO) composite for Li-ion batteries by a simple in situ hydrothermal method. The graphene significantly improves the electrical conductivity and buffers the volume change. The composite shows a large reversible capacity and excellent cyclic stability. At the current density of 100 mA g(-1), the first discharge and charge capacities are 1469.6 and 879.4 mAh g(-1), respectively. After 55 cycles, the rodlike MnO2/RGO composite could deliver reversible capacity as high as 528.7 mAh g(-1) at the current density of 100 mA g(-1), corresponding to the capacity fading of only 0.8%. The superior electrochemical performance is the joint result of the high capacity of MnO2 and excellent electrical conductivity of RGO.