Abstract
We have used the co-precipitation technique to synthesize nanocrystalline Co-doped CeO2 dilute magnetic semiconductors with Co concentrations ranging from 0.0-0.07. X-ray diffraction patterns (XRD) demonstrate that all the samples display single phase cubic structure without any impurity phase. Average particle sizes calculated from XRD and transmission electron microscopy (TEM) studies showed a gradual decrease with increase in Co ions concentration. UV-visible optical spectroscopy measurements reflect an energy band gap, which decreases with the increasing concentration of dopant (x <= 0.03). Raman spectra show an intensity loss of classical CeO2 vibration modes, which is an indication of considerable structural modifications and disorder in CeO2 lattice. Magnetic measurements revealed that all the samples exhibit a weak ferromagnetism at room temperature.