Preparation mechanism and luminescence of Sr₂SiO₄: Eu phosphor from (Sr, Eu)CO₃@SiO₂ core-shell precursor

Yunsheng Hu, Weidong Zhuang, Jianhua Hao, Xiaowei Huang, Huaqiang He

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DOI: 10.4236/ojic.2012.21002                

Abstract

Sr₂SiO₄: Eu phosphor for white light emitting diodes (LEDs) was synthesized by employing an as-prepared (Sr, Eu)CO₃@SiO₂ core-shell precursor as starting materials, and the effect of the core-shell precursor was also discussed on the crystal structure, particle morphology and luminescent properties of the resultant phosphor. The results showed that the hybrid β- and α′-Sr₂SiO₄: Eu phosphor with fine particle size and narrow distribution could be obtained at a lower firing temperature than that in conventional solidstate reaction method, and its formation mechanism was deduced to be (Sr, Eu)CO₃ diffusion controlled reaction process. Responded to its hybrid crystal structure, this phosphor exhibited the combined luminescence of β- and α′-Sr₂SiO₄: Eu.

Keywords

Phosphor; Precursor; Core-Shell Structure; Preparation Mechanism; Luminescence

Conflicts of Interest

The authors declare no conflicts of interest.

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