Magnetic behavior of Mg and Co modified ferrites

OLIVA, M.I.; CARRARO, P.M.; AGU, U.

Buenos Aires

Workshop; X Latin American Workshop on Magnetism, Magnetic Materials and their Applications; 2013

Iron mixed oxides can be synthesized by thermal decomposition of metals of interest dual-layer hydroxides (HDC) air atmosphere. The HDC have the general chemical [M2+(1-x) M3+x (OH)2] A-nx/n). m.H2O] where M is a metal (di or trivalent) and A is the anion, usually carbonate. The advantage that the application of these solids as precursor materials is the great dispersion of the iron mixed oxides. Many parameters can be modified during the preparation of the HDC, as the composition, and several variables of the method of synthesis, thus obtaining materials with specific properties, with potential technological applications. In this work we study the magnetic behavior and changes in the structure of ferrites modified with Mg and Co obtained from HDC precursors produced by different methods of synthesis. The structural changes are studied by x-ray diffraction, morphology and final composition through the use of an electron microprobe and magnetic properties were measured at room temperature in a vibrating sample magnetometer (VSM). A small difference in the crystallinity of oxides was observed, those obtained after hot water treatment in autoclave (AC) presented a more ordered structure than those obtained by aging at ambient temperature (TA). HDC precursors aged at room temperature (TA) generate oxides whose samples have lower coercivity and lower saturation magnetization than aging in autoclave (AC). Also Fe2 + by Co2 + replacement causes an increase in the coercivity, saturation magnetization and remanence magnetization.