Synthesis and Luminescence of Sr2Si5N8:Eu2+ Red Phosphor for High Color-Rendering White LED

고연색 LED용 적색 Sr2Si5N8:Eu2+ 형광체의 합성 및 발광특성 연구

  • Lee, Sung Hoon (R&D Business Lab, Hyosung Corporation) ;
  • Kim, Jong Su (Department of Display Engineering, Pukyong National University) ;
  • Kang, Tae Wook (Interdisciplinary Program of LED and Solid State Lighting Engineering, Pukyong National University) ;
  • Ryu, Jong Ho (Department of Display Engineering, Pukyong National University) ;
  • Lee, Sang Nam (Department of Graphic arts and Information Engineering, Pukyong National University)
  • 이성훈 ((주)효성) ;
  • 김종수 (부경대학교 융합디스플레이공학과) ;
  • 강태욱 (부경대학교 LED협동과정) ;
  • 류종호 (부경대학교 융합디스플레이공학과) ;
  • 이상남 (부경대학교 인쇄공학과)
  • Received : 2017.10.30
  • Accepted : 2017.12.21
  • Published : 2017.12.31

Abstract

Red phosphors, $Sr_2Si_5N_8:Eu^{2+}$, were synthesized as a single-phase crystal structure by optimizing carbon and $Eu^{2+}$ contents in a carbothermal reduction nitridation method. With increasing $Eu^{2+}$ contents, the photoluminescence spectra were red-shifted from 600 nm peak for 1 mol% for to 700 nm for 7 mol%. It was suggested that this red shift is attributed to the energy transfer from one low-energy sited $Eu^{2+}$ (1) to other high-energy sited $Eu^{2+}$ (2). Finally, the best red sample (620 nm emission peak and 80 nm half width for 3 mole% of $Eu^{2+}$) was packaged on a Blue LED together with two additional green and yellow phosphors, the fabricated White LED showed a high color-rendering index of 90 and white color coordinates of x= 0.321 and y = 0.305.

Keywords

References

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