Turning of luminescence properties of Ba2V2O7 phosphors by co-doping Eu3+/Dy3+ ions

A series of Ba1.97–xEu0.03DyxV2O7 (x = 0.01, 0.02, 0.03, 0.04 and 0.05) phosphor materials were synthesized by hydrothermal method. Phase purity, structural, optical and luminescence characteristics of as-synthesized phosphors have been studied using powder X-ray diffraction (PXRD), UV–visible spectroscopy and fluorescence spectrometry. The XRD patterns of as-synthesized phosphors were indexed and predicted as triclinic structure. The broad absorption in the UV region was originated from [VO4]3− group charge transfer and the sharp peaks observed in the visible to near-infrared (NIR) region was originated from Eu3+/Dy3+ ions charge transfer. In photoluminescence (PL) spectra, the broad emission peak observed from 400 to 570 nm was due to the charge transfer band of [VO4]3− group. A sharp peak observed from 570 to 710 nm were due to the charge transition of Eu3+/Dy3+ ions. The PL spectra recorded for different excitations at 268, 344, 335, 346, 346 and 339 nm, emitted bluish white colour with slight changes in its Commission International de l′Eclairage coordinate values. The white colour emission of Ba1.97–xEu0.03DyxV2O7 phosphors was observed by the irradiation under the UV light 365 nm. Hence, the results have suggested that the as-prepared phosphor materials are the potential candidates in the fabrication of a UV or near-UV chip-excited white light-emitting diode.