Dependence of optical properties on the composition of (Ba1-x-ySrxEuy)Si2O2N2 phosphors for white light emitting diodes

作者：Zhang, Mei^*; He, Xin; Luo, Jianyi; Zeng, Qingguang

来源：Materials Chemistry and Physics, 2014, 147(3): 968-973.

DOI：10.1016/j.matchemphys.2014.06.044

• Optical materials
• Solid-solution
• Reaction synthesis
• Spectroscopic methods

BaSi2O2N2: Eu2+ is an efficient phosphor because of its high quantum yield and quenching temperature. Partial substitution of Ba2+ by Sr2+ is the most promising approach to tune the color of phosphors. In this study, a series of (Ba1-x-ySrxEuy)Si2O2N2 (x = 0.0-0.97, y = 0.00-0.10) phosphors are synthesized via high-temperature solid-state reactions. Intense green to yellow phosphors can be obtained by the partial substitution of the host lattice cation Ba2+ by either Sr2+ or Eu2+. The luminescent properties and the relationships among the lowest 5d absorption bands, Stokes shifts, centroid shifts, and the splitting of Eu2+ are studied systematically. Then, based on (Ba1-5-ySrxEuy)Si2O2N2 phosphors and near-ultraviolet (similar to 395 nm)/blue (460 nm) InGaN chips, intense green-yellow light emitting diodes (LEDs) and white LEDs are fabricated. (Ba0.37Sr0.60)Si2O2N2: 0.03Eu(2+) phosphors present the highest efficiency, and the luminous efficiency of white LEDs can reach 17 lm/w. These results indicate that (Ba1-x-ySrxEuy)Si2O2N2 phosphors are promising candidates for solid-state lighting.

• 出版日期2014-10-15
• 单位五邑大学