STRUCTURAL AND DIELECTRIC PROPERTIES OF MgAl_2-2xY_2xO₄ NANOPARTICLES

A series of Nano MgAl_2-2xY_2xO₄ (x = 0.00, 0.07 & 0.10) was prepared by chemical co-precipitation technique. X-ray diffraction (XRD) analysis reveals that a secondary phase appears at x = 0.10 along with the spinel phase. The broad peaks in the XRD pattern and particle size analysis by Transmission electron microscopy (TEM) confirmed nanocrystalline nature of the samples. Room temperature dielectric response as a function of frequency (1 kHz to 1MHz) shows that dielectric constant loss tangent and ac conductivity decreases with increase in yttrium content. The variation of dielectric constant as a function of frequency indicates the dielectric dispersion due to Maxwell-Wagner Polarization. The variation of AC conductivity with frequency suggests the conduction mechanism due to small polaron hopping.