Synthesis, Characterization And Properties Research Of Iron Oxide Composite

Iron oxide is an important magnetic material, and has broad application prospects in the adsorption, catalysis, lithium-ion batteries, sensors and biomedicine. However, we found that iron oxide existed different degrees of defect by further research. The effectively assembling of iron oxide and other nano-micron structure can achieve excellent performance and multiple functional of iron oxide nanomaterials. Therefore, the explorationof iron oxide composites has important significance.In this paper, porous α-Fe2O3 nanoplates, Fe3O4 magnetic material, Graphene/Fe3O4 nanocomposites were successfully synthesized by solvothermal method. The structure and properties of magnetic nanomaterials were characterized by a variety of analytical methods and their adsorption, photocatalysis, magnetic and electrochemical properties were investigated. The detail process is as follows.1. Uniform porous α-Fe2O3 nanoplates were successfully synthesized via a facile solvothermal method and calcination technology. The as-prepared samples were further characterized by various analytical techniques. The results showed that the as-prepared samples had a hexagonal phase structure and exhibited a porous plate-like morphology. The photocatalytic activity experiments toward some organic dyes(such as Safranine T, Pyronine B, Methylene Blue and Rhodamine B) indicated that the porous α-Fe2O3 nanoplates could degrade these dyes to various degrees, especially the degradation ratio of Rhodamine B almost achieves to 100% under UV irradiation. Moreover, the porous α-Fe2O3 nanoplates exhibited a ferromagnetic behavior.2. Fe3O4 nanododecahedrons were successfully synthesized via a facile solvothermal method. The as-prepared samples were further characterized by various analytical techniques. The results show that PEG-10000 can modulate the growth ratio of crystal plane by absorbing on the specific plane and the nanododecahedrons can be obtained under the help of PEG-10000. In addition, the as-prepared Fe3O4 nanododecahedrons not only could high-ef?ciently degrade some organic dyes(such as Safranine T and Congo red), but also have magnetic response, which could easily be separated from the dyes aqueous solution with the assistance of the magnet force.3. Nanosized Fe3O4 have been successfully synthesized through a simple hydrothermal method. The results showed that the as-prepared Fe3O4 nanoparticles were cubic structure and had the mean diameter of 30 nm. The photocatalytic activity experiments toward some organic dyes(such as Methylene Blue, Safranine T) indicated that the as-prepared Fe3O4 nanoparticles exhibited superior photocatalytic degradation activity and also had good stability after three cycles. Moreover, the as-prepared Fe3O4 nanoparticles showed high magnetization saturation value at room temperature, which made it possible to realize convenient separation in water treatment process and thus reduced secondary pollution.4. Graphene/Fe3O4(GN/Fe3O4) composites were successfully prepared by a facile one-step solvothermal route. The characterization results showed that as-prepared Fe3O4 nanoparticles with the mean size of 40 nm were dispersed evenly on the graphene sheets, which avoided the close restacking of graphene sheets effectively. The photocatalytic activity experiments toward some organic dyes(such as Pyronine B, Methylene Blue, Methyl Orange and Rhodamine B) indicated that the as-prepared GN/Fe3O4 composites exhibited superior catalytic activity under UV irradiation, its degradation ratios for these dyes almost all achieved to above 90%. And the as-prepared GN/Fe3O4 composite has good stability and can be reused with almost little loss. In addition, the as-prepared GN/Fe3O4 composite also has the ferromagnetic behaviors and could be separated from the dye solution with the aid of external magnet, which may be a good candidate in the preparation of the recycled catalysts and eliminating catalyst pollution.5. Graphene/Fe3O4(GN/Fe3O4) nanocomposites with enhanced lithium-storage performance were synthesized successfully by a facile one-step solvothermal method, where the reduction process of graphite oxide into graphene was accompanied by the generation of Fe3O4 nanoparticles. The as-prepared nanocomposites were characterized by various analytical techniques. The results showed that the as-prepared Fe3O4 nanoparticles with a diameter as small as 30 nm were densely and uniformly deposited on graphene sheets which effectively prevented Fe3O4 nanoparticles from aggregating. The as-prepared GN/Fe3O4 nanocomposites were utilized as anodes for lithium ion cells. The GN/Fe3O4 nanocomposites exhibited high reversible capacity of 1165 m Ahg-1 at current density of 100 m Ag-1 and good stability for over 70 cycles, in contrast with that of the pure-Fe3O4 nanoparticles which demonstrated rapid degradation to 431 m Ahg-1 after 70 cycles. Furthermore, the composite showed good rate capability. In addition, the as-prepared graphene/Fe3O4 nanocomposites exhibited a ferromagnetic behavior and could be separated from solution by a magnet.