Abstract:

Pure EuBO₃ polycrystals were prepared by hydrothermal method. The crystal structure, morphology, valence state and luminescence property were investigated via X-ray diffractometer(XRD), scanning electron microscope(SEM), X-ray photoelectron spectrometer(XPS) and photoluminescence(PL) spectrometer, respectively. The results indicate that the crystal structure of sample is hexagonal and the morphologies can be manipulated under different alkalinity condition. The orientation of the samples is along [100] and [002] direction when NaOH or NH₃·5H₂O is used as mineralizer, respectively. Tunable luminescence property was observed by varying the excitation wavelength. Red light can be generated when the sample was excited with a 270 nm light. Because of mixed valence of the Eu, EuBO₃ presents blue emission under the excitation wavelength of 360 nm.

Key words: EuBO₃, Mixed valence, Tunable luminescence property