XRD study of structural transformation in NiZn ferrrites synthesised by xerogel

M DEL C. AGUIRRE, S.P.SILVETTI, G.POZO LÓPEZ AND S.E.URRETA

20-24 noviembre , Arica-Chile

Simposio; SARX, LATIN AMERICAN SEMINARY OF ANALYSIS BY X-RAY TECHNIQUES; 2006

Abstract By using the sol-gel method we have obtained nanoparticles of stoichiometric (Zn0.5 Ni0,5 Fe2O4)x -mixed ferrite (x=0,05; 0,10; 0,20; 0,50), dispersed in an amorphous (SiO2)1- x matrix (nanocomposites).The crystalline phases obtained in the composites were identified by X-ray diffraction (XRD). The pattern was recorded from 10o to 100o with a step size of 0.2o and a scanning rate of 10s per step. After indexing the diffraction maximums and taking into consideration the values of the corresponding Bragg angles, the resulting spectra demonstrate that in all cases NiZn ferrite is formed in the SiO2 matrix as a single phases. At the same time, we can observe that the ferrite is well crystallized and the SiO2 matrix is in amorphous state. The result indicates that the NiZn ferrites required calcination at high temperature. No other phases were detected in the system through XRD. Crystalline sizes of the composite are calculated from X-ray peak broadening of the (311) diffraction peak using Scherrer´s formula. The diffraction peaks are broadened wit increase of silica content suggesting that the crystalline size of the ferrite decreases with increasing silica content.