▎ 摘 要
A one-step high-temperature solvothermal process (can be used up to 400 degrees C) has been explored for the preparation of Fe3O4/graphene composites. The influence of high temperature (>230 degrees C) on the structure, morphology and electrochemical properties of the resulting Fe3O4/graphene composites was investigated by XRD, SEM, TEM and N-2 adsorption-desorption measurements. Electrochemical performances of the as-prepared Fe3O4/graphene composites at different temperatures were evaluated in coin-type cells as anode materials for lithium-ion batteries. In comparison with the traditional solvothermal method (<240 degrees C), the high-temperature method does not require an additional calcination process yet it still could result in Fe3O4/graphene composites with pure phase and excellent electrochemical properties. A preferred solvothermal temperature of 280 degrees C has been deduced based on a series of control experiments. The Fe3O4/graphene composite derived at 280 degrees C exhibited a high reversible capacity of 907 mA h g(-1) at 0.1 C (92.6 mA g(-1)) even after 65 cycles, showing outstanding cycle stability. It also exhibited a high rate capability of 410 mA h g(-1) at 2 C (1852 mA g(-1)). The role of the graphene substrates in improving the electrochemical properties of the composite is discussed based on the morphology, structure, phase and electrochemical property studies.