Wanquan Jiang et al 2009 Smart Mater. Struct. 18 125013 doi:10.1088/0964-1726/18/12/125013
Wanquan Jiang1,3, Zhen Cao1, Rui Gu2, Xingzhu Ye2, Cuifeng Jiang1 and Xinglong Gong2,3
Show affiliationsIn this paper, a simple route to synthesize hollow spheres of ZnFe2O4 without the assistance of a template is reported. The crystal structure and morphology of these particles were characterized by x-ray diffraction (XRD), transmission electron microscopy (TEM), and field emission scanning electron microscopy (FE-SEM). It was found that the final products were hollow spheres with perfect morphology, and their size and the thickness of their shells decreased with the increase of urea precursor. Ferromagnetism was observed from the magnetic hysteresis loops of the ZnFe2O4 hollow spheres at room temperature. The possible formation mechanism of the hollow spheres is discussed. In addition, ZnFe2O4 magnetorheological (MR) fluids were prepared and then their MR effect was investigated on a rotational rheometer equipped with a magnetic field generator.
81.20.-n Methods of materials synthesis and materials processing
61.50.-f Structure of bulk crystals
83.80.Gv Electro- and magnetorheological fluids
75.60.Ej Magnetization curves, hysteresis, Barkhausen and related effects
Soft matter, liquids and polymers
Issue 12 (December 2009)
Received 3 July 2009, in final form 3 September 2009
Published 6 October 2009
Wanquan Jiang et al 2009 Smart Mater. Struct. 18 125013
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