Influence on Doping of 0.4 mol of Co in ZnO Aiming their Application in DMS

Abstract

This paper proposes evaluate the effect on doping of 0.4mol of Co in ZnO, Aiming to use in diluted magnetic semiconductor (DMSs), so for this purpose, an evaluation of the characteristics: structural, morphological and magnetic was investigated. The samples were synthesized by combustion reaction using urea as fuel and an electric heater as source of heating. During the synthesis was performed measurements of temperature and time of combustion flame. The samples were characterized by X-ray diffraction (DRX), adsorption of nitrogen (BET), scanning electron microscopy (SEM), particle size distribution and magnetic measurement. The maximum temperature, and reaction time were, 520 oC and 240 s. The data of the XRD showed how phase majority the ZnO, with crystallite size of 27 nm and trace of second phase CoCo2O4. Presented superficial area of 33.5 m2/g, with morphology consisting of agglomerates in the form of balls smaller than 5 μm. The sample presented behavior ferrimagnetic with saturation magnetization of 0.32 emu/g, type of a magnetic semiconductor.

Experimental design to evaluate the efficiency of maghemite nanoparticles incorporation in styrene‐divinylbenzene copolymers

“…Table 4 presents the results of Ms, Mr and Hc of the styrene divinylbenzene resins synthesized in line with the factorial design. According to Machado (2015), 34 through the magnetization curves it is possible to observe the dependence of magnetization M as a function of the applied magnetic field H 38–39 …”