Effect of Lanthanum Substituted CoFe<sub>2-x</sub>La<sub>x</sub>O<sub>4</sub> on Change of Structure Parameter and Phase Formation

Abstract

In this research, CoFe2-xLaxO4-based smart magnetic material has been developed which will be applied as a microwave absorbing material. This smart magnetic material is an artificial advanced material which has properties such as electromagnetic waves so that it is able to respond to the presence of microwaves through the mechanism of spin electron resonance and wall resonance domain. This smart magnetic material consists of a combination of rare earth metal elements (spin magnetic in theforbital configuration) and transition metal elements (spin magnetic in thedorbital configuration) with a semi-hard magnetic structure. This semi-hard is a characteristic of magnetic properties which is between hard magnetic and soft magnetic properties. This characteristic of the semi-hard magnetic properties is needed so that this material has the ability to absorb microwaves. Substitution of lanthanum into cobalt ferrite CoFe2-xLaxO4for La3+(x = 0 - 0.8) has been synthesized using the solid reaction method through mechanical deformation techniques. The refinement result of X-ray diffraction shows that the sample contains 2 phases with increasing of x compositions. Particle morphology and elementary analysis were observed respectively by using a scanning electron microscope (SEM) and energy dispersive spectroscopy (EDS). It was concluded that the effect of La substitution on CoFe2-xLaxO4resulted in changes in the crystal structure parameters and phase transformation as a function of composition.