| Graphene oxide has a potential future as energy converse material, for it is easily be modified, and have a huge specific surface area, high electrochemical stabilities, excellent electrical, perfect thermal, great mechanical properties and so on after be reduced, reduced graphene oxide have a similar property just like graphene. Graphene oxide can be produced on a large scale at low cost. Many kinds of Complex materials based on graphene oxide are been studied widely and are applied for li-ion battery, supercapacitors, photocatalyst, water splitting, fuel cells and solar cells.Fe2O3 is particularly interesting as anode material for li-ion battery due to its high theoretical capacity (1005 mA h g-1), environmental friendly, safe, and low cost. But Fe2O3 has a low electrical property and volume change in the process of charge and discharge, which deeply limit its application as anode material. Researchers find a hollow structure and electrical materials constructed Fe2O3 can promote the stability of anode materials by modify the electrical property and volume change in the process of charge and discharge, and the electrical property of Fe2O3 can be deeply strengthen.The low charge and discharge rate of li-ion battery limit its application in situations which need a fast charge and discharge rate compared with other energy storage devices, while supercapacitors are good devices.A hollow structure of metal oxide can be contribute for a fast moving rate of electron and ion as anode materials and can buffer volume change in the process of charge and discharge, so as to release the fast decrease of capacity, and good for retain the stability of material, so many researches are going on.A constructed structure of graphene based materials is particularly interesting. The li storage property of Metal oxide and electrical property of graphene can been taken full advantage. Mechanical properties of Graphene can release the volume and excellent electrical properties can strength the electrical property of complex materials as structural framework, so as to improve its electrochemical property, researches show its great potential application.In this article, Graphene oxide was used as substrate to prepare graphene-based Fe2O3, the electrochemical properties of the composites were evaluated. The details are as follows:1. Graphene was supported for the anode materials in LIBs, through the one step hydrothermal treatment led to the formation of Fe2O3/RGO. As the anode material in LIBs, the Fe2O3/RGO showed excellent reversible specific capacity of 420 mAh g-1 after 50 cycles at a current density of 100 mA g-1, and maintained the specific capacities of 230 at the ultrahigh current densities of 1000 mA g-1, respectively. The intriguing results can be attributed to the synergistic interaction between Fe2O3 and graphene aerogel, and graphene can improve the electrical property of complex material.2. We improve the situation of the reaction, through change materials, solution, the reaction situation, we success fabricated graphene constructed hollow Fe2O3 spheres with size ranged from 2000 nm to 50 nm and Fe2O3 spheres more than 300 nm show a hollow structure. As the anode material in LIBs, the GHFs showed excellent reversible specific capacity of 950 mAh g-1 after 50 cycles at a current density of 100 mA g-1 and maintained the specific capacities of 640 mAh g-1 at the ultrahigh current densities of 1000 mA g-1, respectively. The intriguing results can be attributed to the hollow structure, uniform dispersion, controllable size of Fe2O3, and the synergistic interaction between Fe2O3 and graphene aerogel, graphene can not only improve electrical property and rate of li-ion, but also release volume change so graphene can improve the electrical property of complex material.3. GHFs was applied as anode material of supercapacitor, a reversible specific capacity of 350 F g-1 after 5000 cycles at a current density of 1A g-1 and maintained the specific capacities of 350 F g-1 arafter 5000 cycles. |
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