Synthesis and photoluminescence of a novel Sr-SiAlON:Eu2+ blue-green phosphor (Sr14Si68−sAl6+sOsN106−s:Eu2+ (s ≈ 7))

A novel Eu2+ activated Sr-SiAlON oxynitride phosphor, with the chemical composition of Sr14Si68−sAl6+sOsN106−s:Eu2+ (s ≈ 7), was synthesized by firing the powder mixture of SrO, SrSi2, α-Si3N4, AlN and Eu2O3 at 1900 °C for 6 h under 1 MPa nitrogen atmosphere. The structure has a typical feature of SiAlON consisting of the host framework which is constructed by a three-dimensional MX4 tetrahedral (M: Si or Al; X: O or N) network, and Sr or Eu2+ ions as the guest ions. It has been shown that the Sr-SiAlON:Eu2+ phosphor has the excitation band covering the range of the ultraviolet light region to 500 nm, and exhibits an intense blue-green color with the emission band centered at about 508 nm. The temperature dependent emission intensity of the Sr-SiAlON:Eu2+ phosphor is better than that of a typical blue-green Ba2SiO4:Eu2+ phosphor. It is demonstrated that Sr-SiAlON:Eu2+ phosphor is very promising for use in white -LEDs.

Research highlights▶ A new Sr-SiAlON:Eu2+ phosphor was found and identified as one of the predicted phases in the composite crystal series. ▶ The photoluminescence properties of obtained new Sr-SiAlON:Eu2+ phosphor were reported. ▶ It is shown that this Sr-SiAlON:Eu2+ phosphor is a promising blue-green phosphor candidate for creating white-light when combined with high-power blue-LED chips.