학회 | 한국재료학회 |
학술대회 | 2015년 봄 (05/14 ~ 05/15, 구미코) |
권호 | 21권 1호 |
발표분야 | F. 광기능/디스플레이 재료 |
제목 | Effect of Some Cations Substitution on Mn4+–doped Mg2TiO4 red phosphor |
초록 | In the past few decades, rapid progress has been made in the fabrication of white-light-emitting diodes (WLEDs) which show superior properties, such as high efficiency, compactness, long operational lifetime, good material stability and environment friendliness. In this study, the red phosphors based on the substitution of some cations in the lattice of magnesium titanate (Mg2TiO4:Mn4+) were prepared through a solid-state method and their photoluminescence properties were investigated. The phosphors were synthesized by annealing at 1500oC for 6 h under air atmosphere using MgO, TiO2 and MnCO3 as raw materials. From X-ray diffraction patterns, it was confirmed that the phosphors of single-phased cubic structure without any impurity phases are formed with the usage of 10 wt%-excess MgO. Photoluminescence spectra indicated that these phosphors are efficiently excited by near UV and visible light absorption in the range from 250 to 600 nm, and emit red light associated with the 2E2 → 4A2 transition at 663 nm. Emission spectra of the Mg2TiO4:Mn4+ phosphors with Mn4+ concentration changes revealed that the optimum Mn4+ concentration based on emission intensity is about 0.3 mol%. To increase the luminance of the phosphors, the diverse cations such as Zr4+, Sn4+, Ce4+ or Zn2+ were partially substituted on Ti4+ or Mg2+ site. As a result, Zn2+ ion was the most effective substituent in enhancing luminance of the phosphor, and its optimum content was 1 mol%. |
저자 | 조주영1, 최성호2, 남산1, 정하균2 |
소속 | 1고려대, 2한국화학(연) |
키워드 | red phosphor; Mg<SUB>2</SUB>TiO<SUB>4</SUB>:Mn<SUP>4+</SUP>; WLEDs |