Preparation of Hexaaluminate Phosphor Particles with Spherical Shape by Gas Phase Reaction Process

기상 공정에 의한 구형 형상의 헥사알루미네이트계 형광체 제조

  • Jung, Dae Soo (Department of Chemical Engineering, Konkuk University) ;
  • Hong, Seung Kwon (Department of Chemical Engineering, Konkuk University) ;
  • Koo, Hye Young (Department of Chemical Engineering, Konkuk University) ;
  • Ju, Seo Hee (Department of Chemical Engineering, Konkuk University) ;
  • Kang, Yun Chan (Department of Chemical Engineering, Konkuk University)
  • 정대수 (건국대학교 화학공학과) ;
  • 홍승권 (건국대학교 화학공학과) ;
  • 구혜영 (건국대학교 화학공학과) ;
  • 주서희 (건국대학교 화학공학과) ;
  • 강윤찬 (건국대학교 화학공학과)
  • Received : 2005.05.02
  • Accepted : 2005.09.07
  • Published : 2005.10.31

Abstract

The morphology and photoluminescence characteristics of green light emitting hexaaluminate phosphor particles prepared by high temperature spray pyrolysis from spray solution with and without ammonium dihydrogen phosphate flux were investigated. The particles prepared from spray solution without flux material had hollow morphology at preparation temperatures between $900^{\circ}C$ and $1,650^{\circ}C$. Ammonium dihydrogen phosphate flux added into spray solution enabled the formation of particles with spherical shape and filled morphology at preparation temperatures between $900^{\circ}C$ and $1,650^{\circ}C$. The hexaaluminate phosphor particles with magnetoplumbite structure were directly prepared by spray pyrolysis from spray solution with ammonium dihydrogen phosphate flux above $1,600^{\circ}C$. Ammonium dihydrogen phosphate flux was effective in improving the photoluminescence intensity of the phosphor particles at low preparation temperatures. The phosphor particles prepared from spray solution with and without flux material by spray pyrolysis under reducing atmosphere at $1,650^{\circ}C$ had comparable photoluminescence intensities with that of the phosphor particles optimized by post-treatment.

Ammonium dihydrogen phosphate 융제의 첨가가 고온 분무열분해 공정에 의해 합성된 녹색 발광의 헥사알루미네이트계 형광체의 형태 및 발광 특성에 미치는 영향을 보았다. 융제를 함유하지 않은 분무용액으로부터 반응기 온도 $900^{\circ}C$ 에서 $1,650^{\circ}C$ 사이에서 합성된 분말은 매우 속이 빈 형태를 가졌다. 반면에 ammonium dihydrogen phosphate 융제를 첨가한 분무용액으로부터 반응기 온도 $900^{\circ}C$ 에서 $1,650^{\circ}C$ 사이에서 합성된 분말은 완벽한 구형 형상을 가지면서 치밀한 구조를 가졌다. 반응기 온도 $1,600^{\circ}C$ 이상에서 ammonium dihydrogen phosphate 융제를 첨가한 분무용액으로부터 마그네토플룸비아트 구조를 가지는 헥사알루미네이트 형광체 분말이 합성되었다. Ammonium dihydrogen phosphate 융제는 저온에서 형광체의 발광 특성을 증가시키는데 효과적이었다. 반응기 온도 $1,650^{\circ}C$의 환원분위기하에서 분무열분해 공정에 의해 직접 제조된 형광체는 융제의 첨가 유무에 무관하게 후열처리 과정을 통해 최적화된 형광체와 유사한 발광 세기를 가졌다.

Keywords

Acknowledgement

Supported by : 한국과학재단

References

  1. Kang, Y. C., Roh, H. S. and Park, S. B., 'Preparation of $Y_2O_3$:Eu Phosphor Particles of Filled Morphology at High Precursor Concentrations by Spray Pyrolysis,' Adv. Mater., 12, 451-453(2000) https://doi.org/10.1002/(SICI)1521-4095(200003)12:6<451::AID-ADMA451>3.0.CO;2-S
  2. Kim, E. J., Kang, Y. C., Park, H. D. and Ryu, S. K., 'UV and VUV Characteristics of $(YGd)_2O_3$:Eu Phosphor Particles Prepared by Spray Pyrolysis from Polymeric Precursors,' Mater. Res. Bull., 38, 515-524(2003) https://doi.org/10.1016/S0025-5408(02)01047-4
  3. Roh, H. S., Kim, E. J., Kang, H. S., Kang, Y. C., Park, H. D. and Park, S. B., 'Vacuum Ultraviolet Characteristics of Nano-sized $Gd_2O_3$:Eu Phosphor Particles,' Jpn. J. Appl. Phys., 42, 2741-2745 (2003) https://doi.org/10.1143/JJAP.42.2741
  4. Kang, Y. C., Roh, H. S. and Park, S. B., 'Use of LiCl Flux in the Preparation of $Y_2O_3$:Eu Phosphor Particles by Spray Pyrolysis,' J. Eur. Ceram. Soc., 22, 1661-1665(2002) https://doi.org/10.1016/S0955-2219(01)00462-9
  5. Shimomura, Y. and Kijima, N., 'High-Luminance $Y_2O_3$:$Eu^{3+}$ Phosphor Synthesis by High Temperature and Alkali Metal Ion-added Spray Pyrolysis,' J. Electrochem. Soc., 151(4), H6-H2(2004) https://doi.org/10.1149/1.1762410
  6. Shimomura, Y. and Kijima, N., 'High-Temperature Spray Pyrolysis of $Y_2O_3$:$Eu^{3+}$ Red Phosphor,' Electrochem. Solid-State Lett., 7(2), H1-H4(2004) https://doi.org/10.1149/1.1633692
  7. Shimomura, Y. and Kijima, N., 'Formation Mechanisms and Control Method of Aluminum-containing Impurity in High-temperature Spray Pyrolysis of $Y_2O_3$:$Eu^{3+}$ Phosphor,' Electrochem. Solid-State Lett., 7(5), H18-H22(2004) https://doi.org/10.1149/1.1669342
  8. Shimomura, Y. and Kijima, N., 'Effect of Ammonium Chloride Addition on Spray Pyrolysis Synthesis of $BaMgAl_{10}O_{17}$:$Eu^{2+}$ Phosphor Without Post-heating,' J. Electrochem. Soc., 151(8), H192- H197(2004) https://doi.org/10.1149/1.1767160
  9. Kang, Y. C., Seo, D. J., Park, S. B. and Park, H. D., 'Morphological and Optical Characteristics of $Y_2O_3$:Eu Phosphor Particles Prepared by Flame Spray Pyrolysis,' Jpn. J. Appl. Phys., 40(6A), 4083-4086(2001) https://doi.org/10.1143/JJAP.40.4083
  10. Chang, H., Lenggoro, I. W., Ogi, T. and Okuyama, K., 'Direct Synthesis of Barium Magnesium Aluminate Blue Phosphor Particles Via a Flame Route,' Mater. Lett., 59(10), 1183-1187(2005) https://doi.org/10.1016/j.matlet.2004.12.024
  11. Zhang, J., Zhang, Z., Tang, Z. and Lin, Y., '$Mn^{2+}$ Luminescence in (Ce,Tb)$MgAl_{11}O_{19}$ Phosphor,' Mater. Chem. Phys., 72, 81-84(2001) https://doi.org/10.1016/S0254-0584(01)00301-7
  12. Smets, B. M. J., 'Phosphors Based on Rare-earths, A New Era in Fluorescent Lighting,' Mater. Chem. Phys., 16, 283-299(1987) https://doi.org/10.1016/0254-0584(87)90103-9