Synthesis and Magnetic Properties of Maghemite (γ-Fe2O3) Short-Nanotubes
1 Key Laboratory of Artificial Micro- and Nano-structures of Ministry of Education, Wuhan University, Wuhan, 430072, People’s Republic of China
2 Center for Electronic Microscopy and School of Physics and Technology, Wuhan University, Wuhan, 430072, People’s Republic of China
Nanoscale Research Letters 2010, 5:1474-1479 doi:10.1007/s11671-010-9664-4Published: 17 June 2010
We report a rational synthesis of maghemite (γ-Fe2O3) short-nanotubes (SNTs) by a convenient hydrothermal method and subsequent annealing process. The structure, shape, and magnetic properties of the SNTs were investigated. Room-temperature and low-temperature magnetic measurements show that the as-fabricated γ-Fe2O3 SNTs are ferromagnetic, and its coercivity is nonzero when the temperature above blocking temperature (TB). The hysteresis loop was operated to show that the magnetic properties of γ-Fe2O3 SNTs are strongly influenced by the morphology of the crystal. The unique magnetic behaviors were interpreted by the competition of the demagnetization energy of quasi-one-dimensional nanostructures and the magnetocrystalline anisotropy energy of particles in SNTs.