Tunable Cathodoluminescence Properties of Tb[sup 3+]-Doped La[sub 2]O[sub 3] Nanocrystalline Phosphors

Nanocrystalline -doped phosphors were prepared through a Pechini-type sol–gel process. X-ray diffraction (XRD), field-emission-scanning electron microscopy (FESEM), photoluminescence, cathodoluminescence (CL) spectra, and lifetimes were utilized to characterize the synthesized phosphors. The XRD results revealed that a pure phase can be obtained at . FESEM images indicated that the phosphors are composed of aggregated spherical particles with sizes ranging from 60 to 100 nm. Under the excitation of UV light and low voltage electron beams (0.5–3 kV), the phosphors showed the characteristic emissions of ( transitions). The CL colors of phosphors was tuned from blue to green by changing the doping concentration of to some extent. The optimum blue CL of phosphors had better Commission International l'Eclairage (CIE) coordinates and higher emission intensity than those of the commercial product (blue, product no. 1047, Nichia Kagaku Kogyo Kabushiki, Japan).