Chen Chuan-Sheng, Liu Yong, Huang Bai-Yun, Lei Ting, Chen Xiao-Hua
State Key Laboratory for Powder Metallurgy, Central South University, Changsha 410083, China.
Guang Pu Xue Yu Guang Pu Fen Xi. 2009 Oct;29(10):2871-4.
Firstly, hydroxide iron precursor was prepared by the co-precipitation method through using nitric iron as the source of iron, ammonia as precipitants, and poly-glycol as dispersant. Secondly, the precursor was calcined at 450 degrees C for 2 h under the protection of nitrogen. Finally, the images and structures of resultant powders were investigated by transmission electron microscopes (TEM), X-ray diffraction (XRD), Raman spectrum and the near-edge X-ray absorption fine structure (NEXAFS), respectively, and the magnetic property of resultant powders was measured by a vibrating sample magnetometer (VSM HH-50). The experimental results of TEM show that the products are composed of Fe2 O3 nano-particles with sizes in the range of 50-100 nm and bamboo-like Fe2 O3 nanobars about 10 nm in diameter. The experimental results of XRD and spectrum illuminate that the structures of products are alpha-Fe2 O3. Moreover, magnetic properties measurement reveals that the products exhibit typical magnetic hysteresis loops of ferromagnetism materials, and their saturation magnetization and coercive force are approximately 64.65 emu x g(-1) and 15.13 Oe, respectively.
首先，以硝酸铁为铁源、氨水为沉淀剂、聚乙二醇为分散剂，采用共沉淀法制备氢氧化铁前驱体。其次，前驱体在氮气保护下于450℃煅烧2小时。最后，分别用透射电子显微镜（TEM）、X射线衍射（XRD）、拉曼光谱和近边X射线吸收精细结构（NEXAFS）对所得粉末的图像和结构进行研究，并用振动样品磁强计（VSM HH-50）测量所得粉末的磁性。TEM实验结果表明，产物由尺寸在50-100nm范围内的Fe2O3纳米颗粒和直径约10nm的竹状Fe2O3纳米棒组成。XRD和光谱实验结果表明，产物结构为α-Fe2O3。此外，磁性测量表明，产物呈现出铁磁性材料典型的磁滞回线，其饱和磁化强度和矫顽力分别约为64.65 emu x g(-1)和15.13 Oe。
