文献类型：期刊文献

英文题名：Preparation, characterization, magnetic property, and M?ssbauer spectra of the β-FeOOH nanoparticles modified by nonionic surfactant

作者：Yang, Y.X.[1,4]; Liu, M.L.[2]; Zhu, H.[1]; Chen, Y.R.[1]; Mu, G.J.[1]; Liu, X.N.[3]; Jia, Y.Q.[1]

机构：[1] Department of Chemistry, Chemistry and Molecule Engineering College, East China University of Science and Technology, Meilong Road 130, Xuhui District, Shanghai 200237, China; [2] Analysis Test Center, Jilin University, Changchun 130023, China; [3] Analysis Test Center, Yangzhou University, Yangzhou 225009, China; [4] State Key Laboratory of Coordination Chemistry, Nanjing University, 210093, China

年份：2008

卷号：320

期号：21

起止页码：L132

外文期刊名：Journal of Magnetism and Magnetic Materials

收录：EI(收录号：20084411662153)

语种：英文

外文关键词：Nanomagnetics - Microemulsions - Nanorods - Crystal structure - Nonionic surfactants - Polyethylene oxides - X ray diffraction - Iron compounds

摘要：βFeOOH nanoparticles have been prepared in a microemulsion system with nonionic surfactant polyoxyethylene(4)nonylphenylether CH3(CH 2)8C6H4O(CH2OCH 2)4H. The powder X-ray diffraction, infrared spectra, and transmission electron microscopic images indicate that the products are 20-30 nm length nanorods with a crystal structure belonging to monoclinic β-FeOOH and lattice parameters of a = 0.9981, b = 0.2948, c = 1.0485 nm and β = 92.26. The size and shapes of β-FeOOH nanoparticles can be manipulated by the surfactant. The modified β-FeOOH nanoparticles are paramagnetic at room temperature and may be antiferromagnetic or weakly ferrimagnetic at lower temperatures. The 57Fe M?ssbauer spectra show that the magnetic structure transforms below 150 K and two kinds of Fe-O octahedra exist in the lattice of the modified β-FeOOH nanoparticles. The numbers of each kind of Fe-O octahedra are not the same at room temperature or at low temperatures. ? 2008 Elsevier B.V. All rights reserved.