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Abstract: Tunable white light of Eu2+ doped SiAlON crystal/glass composite phosphor with blue-yellow dual-emissions was demonstrated by variation of excitation wavelength in this work. The excitation properties of blue emission originated from the transition of Eu2+ ions in the Si–Al–B–O–N glass matrix and that of yellow emission originated from the transition of Eu2+ ions in the SiAlON lattice were investigated, respectively. By varying the excitation wavelength in the range of 330–380nm, white emission was tuned from cool white to warm white for this SiAlON crystal/glass composite phosphor owing to the various excitation properties of these two emission bands. Presented results indicate that this tunable SiAlON crystal/glass composite white-light phosphor might be applied in white LED, combining with UV chips with different emitting wavelengths in the range of 330–380nm. [Copyright &y& Elsevier]

Abstract: Ce3+-doped β-SiAlON blue phosphors with composition of Ce x Si6−z Al z O z N8−z (0.2≤z≤4) at a fixed x=0.01 were synthesized by the gas pressure sintering method. The phases and photoluminescence properties were found to be directly correlated to the z value. Higher z value would result in the formation of AlN polytypoid impurity phases. The optimal z value resides in the range 0.3≤z≤0.5, by which high purity of β-SiAlON phase, good crystallinity and fine grain size were obtained, leading to the best luminescence properties. These phosphors could be a good candidate for application in white light-emitting diodes using InGaN-based near–ultraviolet chips. [Copyright &y& Elsevier]