Synthesis and luminescence investigation of Ba2V2O7-co-doped Dy3+/Eu3+ phosphors for white light-emitting diode applications

This study is aimed to tune the Ba2V2O7 phosphors as the potential candidates in the fabrication of ultra-violet (UV) or near-UV chip-excited white light-emitting diodes (WLEDs) by incorporating Dy3+ and Eu3+ ions in the host lattice. A series of Dy3+ and Eu3+ ions-doped Ba2V2O7 phosphor materials was synthesized using the hydrothermal method. Phase purity, structural, optical, and luminescence characteristics of as-synthesized Dy3+ and Eu3+ ions-doped Ba2V2O7 phosphors were studied using powder X-ray diffraction (XRD), UV-visible spectroscopy, and fluorescence spectrometry. The XRD patterns of Dy3+ and Eu3+ ions-doped Ba2V2O7 phosphors were indexed with triclinic structure as parent Ba2V2O7 phosphor compounds. The broad absorption in the UV region was originated from the parent Ba2V2O7 phosphors ([VO4](3-)) group charge transfer (CT). The overall emission peak centered at 495 nm was due to the charge transfer band (CTB) of the [VO4](3-) group. In addition, the sharp peaks observed in the visible to near-infrared (NIR) region also originated due to CT from the dopant Dy3+/Eu3+ ions. The charge transition of Dy3+ and Eu3+ ions with the parent leads to sharp peaks, observed from 570 to 710 nm. The photoluminescence (PL) spectra recorded at 348 nm emission color tuned from bluish-white to greenish-yellow. The irradiation observed the white color emission of Dy3+ and Eu3+ ions-doped Ba2V2O7 phosphors under the UV light 365 nm. Hence, the results have suggested that the as-prepared Dy3+ and Eu3+ ions-doped Ba2V2O7 phosphors are the potential candidates for fabricating a UV or near-UV chip-excited WLEDs.