Nanocrystalline NiFe2O4 spinel ferrites were synthesized by sol-gel method. The structural and magnetic properties were investigated using X-ray diffraction (XRD), Fourier Transform Infrared (FTIR) spectroscopy, Scann...Nanocrystalline NiFe2O4 spinel ferrites were synthesized by sol-gel method. The structural and magnetic properties were investigated using X-ray diffraction (XRD), Fourier Transform Infrared (FTIR) spectroscopy, Scanning Electron Microscopy (SEM) and Vibrating Sample Magnetometer (VSM). Annealing temperature showed prominent effect on the grain size. The average grain size of NiFe2O4 was observed to increase from 31 nm to 54 nm as the annealing increased from 500℃ to 1000℃. The IR spectra showed the absorption bands corresponding to stretching of tetrahedral and octahedral bands. The magnetic properties were observed to depend strongly on the annealing temperature.展开更多
Nanocrystalline lithium iron oxide LiFeO2 was synthesized using sol-gel method. Rietveld analysis was performed to confirm the different phases associated in the formation of LiFeO2. Quantitative Rietveld refinement r...Nanocrystalline lithium iron oxide LiFeO2 was synthesized using sol-gel method. Rietveld analysis was performed to confirm the different phases associated in the formation of LiFeO2. Quantitative Rietveld refinement revealed that sample contains: 39.9 wt% of cubic α – LiFeO2 phase, 58.5 wt% of monoclinic β - LiFeO2 and tetragonal 1.7 wt%. of γ - LiFeO2. The nanocrystalline nature of the prepared samples was confirmed by SEM analysis. The magnetic properties of LiFeO2 showed ferromagnetic property at room temperature.展开更多
文摘Nanocrystalline NiFe2O4 spinel ferrites were synthesized by sol-gel method. The structural and magnetic properties were investigated using X-ray diffraction (XRD), Fourier Transform Infrared (FTIR) spectroscopy, Scanning Electron Microscopy (SEM) and Vibrating Sample Magnetometer (VSM). Annealing temperature showed prominent effect on the grain size. The average grain size of NiFe2O4 was observed to increase from 31 nm to 54 nm as the annealing increased from 500℃ to 1000℃. The IR spectra showed the absorption bands corresponding to stretching of tetrahedral and octahedral bands. The magnetic properties were observed to depend strongly on the annealing temperature.
文摘Nanocrystalline lithium iron oxide LiFeO2 was synthesized using sol-gel method. Rietveld analysis was performed to confirm the different phases associated in the formation of LiFeO2. Quantitative Rietveld refinement revealed that sample contains: 39.9 wt% of cubic α – LiFeO2 phase, 58.5 wt% of monoclinic β - LiFeO2 and tetragonal 1.7 wt%. of γ - LiFeO2. The nanocrystalline nature of the prepared samples was confirmed by SEM analysis. The magnetic properties of LiFeO2 showed ferromagnetic property at room temperature.
