Controlled synthesis and magnetic properties of bowknot-like CeO_2 microstructures by a CTAB-assisted hydrothermal method

摘要

Bowknot-like CeO_2 microstructures have been successfully synthesized by a CTAB (cetyltrimethyl ammonium bromide)-assisted hydrothermal method using Ce(NO_3)_3·6H_2O as cerium source and urea as mineralizer. X-ray diffraction (XRD) inferred that the synthesized CeO_2 microstructures exhibited a fluorite cubic structure. A scanning electron microscope (SEM) revealed that the CeO_2 microstructures have a bowknot-like microstructure. X-ray photoelectron spectroscopy (XPS) and the Raman spectro-scopy reflected the existence of the oxygen vacancies and Ce~(3+) ions in the bowknot-like CeO_2 microstructures. Magnetization measurements exhibited room temperature ferromagnetism (RTFM) with a saturation magnetization (M_s) of 3.97 × 10~(-3) emu/g and coercivity (H_c) of 200 Oe, which is likely associated with Ce~(3+) ions and oxygen vacancies in the bowknot-like CeO_2 samples.