A new rare-earth oxyborate Ba3BiPbEuO(BO3)4 and the luminescence properties of the Ba3BiPbY1−xEuxO(BO3)4 phosphors†
Abstract
A new rare-earth oxyborate Ba3BiPbEuO(BO3)4 was prepared, and its crystal structure was established by the single-crystal X-ray diffraction method with the following structural data: P63/mmc, a = 5.4305(1) Å, c = 26.3501(3) Å, V = 672.96(3) Å3 and Z = 2. This is a layered material containing two types of layers: one is formed by corner-sharing EuO6 octahedra and BO3 triangles and the other is composed of corner- or edge-sharing (Bi/Pb)O7 hexagonal pyramids and BO3 triangles. These layers and their equivalent partners are alternately stacked along the c-axis, with Ba2+ cations situated in between and within the layers. Furthermore, the phase composition, morphology, and IR, Raman, XPS, and UV–vis absorption spectra of this compound were studied. In addition, solid solutions of Ba3BiPbY1−xEuxO(BO3)4 (0 ≤ x ≤ 1) were prepared via the solid-state reaction method and their photoluminescence properties were investigated. Ba3BiPbYO(BO3)4 and Ba3BiPbEuO(BO3)4 showed blue and reddish-orange luminescence when excited at 242 and 394 nm, respectively. By doping Eu3+ into the Ba3BiPbYO(BO3)4 matrix and changing the Eu3+ doping concentration, luminescence color tunability from blue to orange-red was realized in Ba3BiPbY1−xEuxO(BO3)4 phosphors under excitation at 331 nm. This kind of material with color variability may have potential application in field-emission displays.