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Abstract: In this study, we used oxides (Y2O3, CeO2 and Al2O3) as the raw materials to fabricate YAG:Ce3+ phosphors by a molten salt synthesis (MSS) method. The formation of YAG phase strongly depends on the alumina source and firing temperature. Microstructure characterization indicates that “dissolution-precipitation” mechanism dominates the formation process of YAG in the alkali chlorides melt. Thus, highly active nano-Al2O3 starting powders promote their solution in the melt and guarantee a solute stoichiometric of YAG phase rather than other Y–Al–O compounds. The as-prepared YAG:Ce3+ phosphors show typical yellow emission peaked at 535nm under excitation of 460nm blue light, suggesting that MSS could be a promising method for the preparation of phosphor powders even though oxide raw materials are used. [Copyright &y& Elsevier]

Abstract: Novel single-phased white-light-emitting Ca2.96(P0.99B0.01O4)2:0.04Dy3+ phosphors for light-emitting diode (LED) applications were synthesized by conventional solid-state reactions. The phases and luminescent properties of the obtained Ca2.96(P0.99B0.01O4)2:0.04Dy3+ phosphors were well characterized. The results show that the excited bands of Ca2.96(P0.99B0.01O4)2:0.04Dy3+ phosphor centered at wavelengths of 324nm (6H15/2→4M17/2), 350nm (6H15/2→4M15/2, 6P7/2), 366nm (6H15/2→4I11/2), 387nm (6H15/2→4I13/2, 4F7/2), 427nm (6H15/2→4G11/2), and 448nm (6H15/2→4I15/2). On excitation at 350nm, the emission transitions of Dy3+ consisted of double emission bands, which can be assigned to the transition emissions of 4F9/2→6H15/2 (480nm) and 4F9/2→6H13/2 (572nm). One mol% B3+ dopant improved the luminescence intensity of Ca2.96(PO4)2:0.04Dy3+ phosphor, and the reason was proposed. The developed phosphor has great potential as a single-component white-light-emitting phosphor for UV-light-emitting diodes. [Copyright &y& Elsevier]