Synthesis and luminescent properties of Ln3+ (Ln3+ = Eu3+, Dy3+) -doped Bi2ZnB2O7 phosphors

The new phosphors Bi2ZnB2O7: Ln(3+) (Ln(3+) = Eu3+, Dy3+) were synthesized by solid-state reaction technique. The obtained phosphors were investigated by means of X-ray powder diffraction (XRD), photoluminescence excitation and emission spectra with the aim of enhancing the fundamental knowledge about the luminescent properties of Eu3+ and Dy3+ ions in the Bi2ZnB2O7 host lattice. XRD analysis shows that all these compounds are of a single phase of Bi2ZnB2O7. The excitation and emission spectra of Bi2ZnB2O7: Ln(3+) (Ln(3+) = Eu3+, Dy3+) at room temperature show the typical 4f-4f transitions of Eu3+ and Dy3+, respectively. The hypersensitive transitions of D-5(0)-> F-7(2) (Eu3+) and F-4(9/2)-> H-6(13/2) (Dy3+) are relatively higher than those of the insensitive transitions in Bi2ZnB2O7. It is conceivable that the Bi2ZnB2O7 structure provides asymmetry sites for activators (Eu3+, Dy3+). The optimum concentrations of Eu3+ and Dy3+ ions in Bi2ZnB2O7 phosphors are both x = 0.05.