The production of self-assembled Fe_2O_3-graphene hybrid materials by a hydrothermal process for improved Li-cycling

摘要

An easy and effective strategy is developed to produce α-Fe_2O_3 nanoparticles (NPs) anchored on conducting graphene sheets by a hydrothermal reaction, without any reducing agents. Scanning electron microscopy shows that the α-Fe_2O_3 NPs are 70-85 nm in size and homogeneously anchored on the graphene sheets. As high-performance anodes for lithium-ion batteries, the obtained material exhibits an excellent reversible capacity of ～1050 mAh g~(-1) based on the total mass. Its cycling performance and rate capability are drastically improved, exhibiting a high charge capacity of 1000 ± 50 mAh g~(-1) with no noticeable capacity fading up to 100 cycles in the voltage range 0.1-3.0 V at 50 mA g~(-1). These results high-light the importance of the anchoring of NPs on graphene sheets for maximum use of electrochemically active Fe_2O_3 NPs and graphene for energy storage applications.