A novel Ba3Bi2(PO4)4: Sm3+ orange red-emitting phosphor: Influences of sintering temperature and Sm3+ concentration on microstructures and photoluminescence properties

Abstract

A series of novel Ba3Bi2(PO4)4: Sm3+ phosphors have been prepared by the conventional solid reaction process at different sintering temperature and Sm3+ ion concentration. X-ray powder diffraction patterns, scanning electron microscopy, photoluminescence spectra, decay curve, as well as the temperature-dependent properties and CIE chromaticity coordinate were used to characterize the performance of the as-prepared phosphors. The results show that sintering temperature can significantly affect the phase purity, morphology and photoluminescence performance of the obtained phosphors. The X-ray powder diffraction patterns confirmed that a pure Ba3Bi2(PO4)4 phase could be formed at 980 °C for 5 h in our case. The scanning electron microscopy shows the particle size of the obtained phosphors increases when sintering temperature increases from 900 to 980 °C. And the synthesized Ba3Bi2(PO4)4: Sm3+ is an orange red-emitting phosphor, which can emit 600 nm orange red light under the excitation of 403 nm. Moreover, as the Sm3+ ion concentration increases, the emission intensity reaches the maximum at x = 0.07. The luminescence lifetime of Ba3Bi2(PO4)4: 0.07Sm3+ phosphor was determined to be 1.978 ms. Meantime, the Sm3+ doped Ba3Bi2(PO4)4 phosphor has a good thermal stability with the thermal activation energy is 0.21 eV. The CIE chromaticity coordinate was calculated located in the orange reddish region, which indicated that the Ba3Bi2(PO4)4: Sm3+ phosphors have a potential application in white light emitting diodes.