Characteristics of cobalt ferrite nanoparticles on graphene and graphene oxide prepared by one-pot synthesis.

• Main Authors: Yu-Ting Hsu, 徐鈺婷
• Other Authors: Cheng-Hsiung Peng
• Format: Others
• Language: zh-TW
• Published: 2014
• Online Access: http://ndltd.ncl.edu.tw/handle/27475052363466166659

碩士 === 明新科技大學 === 化學工程與材料科技系碩士班 === 102 === Magnetic nanoparticles get a lot of attention due to their magnetic, low toxic and bio-compatible properties. Graphene is also considered to be a potential two dimensional materials. Combination of magnetic NPs and the grapheme, such a composite can be served as potential candidate in application of bio-material, energy-storage material, and water treatment. In this thesis, magnetite and cobalt NPs were grown successfully on the grapheme. In this thesis, a one-pot fast synthesis of Fe3O4 nanoparticles (NPs) on graphene/graphene oxide asisted by microwave has been demonstrated. Through the examination of the X-ray diffraction (XRD), scanning electron microscopy (SEM), and Fourier transform infrared spectroscopy (FTIR) on the Fe3O4/graphene composites, the reaction temperature play an important role for the synthesis of Fe3O4/graphene composite with FeCl3 as the reactant. At the reaction temperature of 160 °C 30 min, the nucleation rate of Fe3O4 on graphene is low. Above the reaction temperature of 180 °C, the Fe3O4 NPs can anchor on the graphene successfully. According to the observation of SEM, the Fe3O4 particles density increase from 40 to 100 No./cm2 as the reaction temperature was elevated from 180 °C to 200 °C. The ratio of FeCl3 to graphene also enhanced the nucleation ratio of Fe3O4 on graphene. Thought different ratio of FeCl3 to CoCl2 at the fixed amount of precursor weight to graphene, FeO : Co nanoparticles can grow on the graphene with CoCl2 as the precursor of metal ion, the Co/graphene nanoparticles can be prepared at the temperature of 200 °C. After annealed at 700 °C, the Co NPs will transform into Co3O4 NPs. The Fe3O4 NPs show the ploy-crystalling structure of Fe3O4 on the graphene, and conformed by the examination of XRD. According to the analysis of vibrating sample magnetometer (VSM), the saturation magnetization increases from 0.22 to 13.13 emu/g as the reaction temperature increases from 160 to 200°C. The saturation magnetization can reach 45.32 emu/g for the sample with a mass Fe3O4/graphene ratio of 8.