Abstract
Spinel type ferrites of ZnFe2O4 and NiFe2O4, and also α-Fe2O3 with balloonshape were prepared by coating the ethylene glycol (EG) solution of correspondingmetal chlorides onto carbon balloons with size of 53-75μm and heating upto 950°C in the flow of oxygen. The ZnFe2O4 balloons prepared by a solid-statereaction between the balloons of α-Fe2O3 and ZnO had a characteristic wavylinesurface texture, though those prepared directly from the mixed EG solutionof ZnCl2 and FeCl3 had smooth surfaces. The NiFe2O4 balloons were preparedfrom the mixed solution of NiCl2 and FeCl3.
