EPR and optical studies of pure MgFe_2O_4 and ZnO nanoparticles and MgFe_2O_4-ZnO nanocomposite

摘要

A comprehensive EPR and optical studies of pure MgFe2O4 and ZnO nanoparticles and MgFe2O4-ZnO nanocomposite have been done in order to explore its future possibilities of applications. Pure MgFe2O4 and ZnO nanoparticles have been synthesized using Sol-Gel method. MgFe2O4-ZnO nanocomposite has been prepared using water dispersed pure MgFe2O4 nano seeds (previously synthesized) by ultrasonication. Effect of introducing zinc oxide in pure MgFe2O4 nanomatrix on structural properties was investigated using X-ray diffraction and transmission electron microscopy techniques. They confirm the cubic spinel structure of both pure and ZnO imbedded MgFe2O4 samples. UV-Visible and photoluminescence spectra show that the band gap of composite is tuned and more useful for photocatalytic applications. FTIR spectra indicate the presence of absorption bands in the range 390-561 cm(-1), which is a common feature of spinel ferrite. The energy dispersive spectroscopy analysis confirms the composition of specimen. Further, the investigation of electronic and magnetic properties of the powdered samples is done using electron paramagnetic resonance spectroscopy. Change in g value, peak-to-peak line width (H-pp), resonance field (H-r) and spin-spin relaxation time (T-2) give useful information.