Structural, magnetic and electric characterization of YBaCo4-xNixO7+δ (x=0; 0.1; 0.2)

TORRE, L. M.; AURELIO, G.; SÁNCHEZ, R. D.; BAUDELET, F.

Workshop; Latinamerican Workshop on Magnetism and Magnetic Materials LAW3M; 2013

In recent years, the cobaltite “114”, named after the formula LnBaCo4O7+δ (Ln: rare earth or Y), has received considerable interest due to two attractive phenomena: i) it exhibits magnetic frustration and ii) kinetics of absorption/desorption of oxygen is very appropriate for several technological application as for example, oxygen storage. Recent structural studies show that these oxides can crystallize in two types of structures (trigonal or orthorhombic), according to its oxygen content. The parameter (δ) is modified according to the synthesis conditions, making the synthesis is critical for obtaining a stoichiometric compound. The difference in oxygen content are reflected not only in structure but in also in changes in physics properties. Besides the oxygen content, the doping of the Co site with magnetic ions produces other interesting changes in the material properties, which is a topical issue in current literature. In this work we present a study of the effects on the magnetically and electrical properties when we have a as function of oxygen stoichiometry in sample with and without doping in the Co site. We will focus our analysis on the effects of oxygen content on the system crystalline structure, its influence on magnetism and electrical transport as well as the influence of doping with another magnetic ion, Ni2+. The samples were synthesized under different conditions in order to the control the oxygen content, which was studied by thermogravimetry, and we performed a thorough characterization through characterized using X-ray diffraction, energy dispersive spectroscopy and magnetization and resistivity measurements. These result allow us to interpret the magnetic and electrical behavior of the different samples studying the effect of oxygen non-stoichiometry and doping with Ni2+.