Optical Properties of the Sr₂MgSi₂O₇:Eu⁺ Phosphor Coated with SiO₂ Nano-Particles

Abstract

We investigated the effects of the SiO₂ surface coating on the optical properties of Sr₂MgSi₂O₇:Eu⁺ phosphor which is used for a white light source in the blue LED chip. A modified sol-gel method was used for the surface coating of the commercial yellow phosphor with SiO₂. The experimental results suggest that the surface coating of phosphors with SiO₂ nano-particles leads to an increase in the intensity of the 550 nm peak. It is of interest that this increasing tendency depends on the concentrations of the colloidal solution. Thus, the surface coating of phosphors is a way for improving the luminance of the white LED.

Keywords:

• Nano-particles
• SiO₂
• Sr₂MgSi₂O₇:Eu⁺ phosphor
• surface coating
• white light

Acknowledgments

This work was supported by Korea Research Foundation (KRF) grant funded by the Korea government (MEST) (No. 2009-0072606). The work was also supported by the Regional Innovation Center Program (ADMRC) of the Ministry of Knowledge Economy, Republic of Korea.