Photoluminescent properties of Pr3+ activated Y2WO6 for light emitting diodes.

A series of Pr 3+ activated Y 2 WO 6 phosphors are prepared by solid state reaction method. The crystalline phase and luminescent properties of samples are discussed by X-ray diffraction spectra and photoluminescence spectra, respectively. The photoluminescence excitation spectrum indicates that the sample can absorb both UV and blue light. And the samples emit a blue emission of WO 6 6 − and the characteristic red emission of Pr 3+ . The partial quenching of the other prominent blue luminescence from 3 P 0 state is ascribed to a radiationless relaxation pathway involving a low-lying Pr 4+ –W 5+ intervalence charge transfer (IVCT) state. Through adjusting the excitation wavelength, Y 2 WO 6 : Pr 3+ can not only emit warm white light with CIE coordinates of (0.33, 0.37) but also show bright red emission with CIE coordinates of (0.66, 0.33). In addition, the thermal properties of the samples are also investigated in detail. The results show that the application as a white and red component for white light emitting diodes is proposed. [ABSTRACT FROM AUTHOR]