Ce1-xCoxO2-δ Nanorods Grown by Electrochemical Deposition and Their Magnetic Properties

Magnetically doped CeO2 is a promising dilute magnetic semiconductor as CeO2 has a face-centered cubic system and a high dielectric constant and is a transparent rare-earth oxide. In this contribution we first report the synthesis of room temperature ferromagnetic Ce1-xCoxO2-delta (0< 0.10) nanorods prepared via electrodeposition route. These Ce1-xCoxO2-delta nanorods were thoroughly characterized by X-ray diffraction (XRD), field emission scanning electron microscopy (FE-SEM), transmission electron microscopy (TEM), optical transmission spectroscopy, and magnetic measurements. TEM measurements show these prepared Ce1-xCoxO2-delta nanorods are high crystallinity and single crystalline. The results of optical transmission spectra show the prepared Ce1-xCoxO2-delta nanorods are transparent in the visible regime. The magnetic measurements show the prepared Ce1-xCoxO2-delta nanorods exhibit ferromagnetic property with a high Curie temperature of about 870 K and a giant magnetic moment. In addition, the results in this paper show the ferromagnetism of the prepared Ce1-xCoxO2-delta nanorods can be obviously adjusted by the structural defects, indicating oxygen vacancies could be involved in magnetic coupling between Co ions. The magnetic properties of various Ce1-xCoxO2-delta nanostructures were also studied, and Ce1-xCoxO2-delta nanorods exhibit the larger H-c and M-r values and show promising dilute magnetic semiconductor materials.