| 학회 | 한국재료학회 |
| 학술대회 | 2015년 가을 (11/25 ~ 11/27, 부산 해운대그랜드호텔) |
| 권호 | 21권 2호 |
| 발표분야 | F. 광기능/디스플레이 재료 |
| 제목 | Photoluminescence Properties of YAGG:Ce Phosphors on Al/Ga Ratio Changes |
| 초록 | In recent years, light emitting diodes (LEDs) have been extensively studied for the solid-state lighting applications due to their benefits such as low energy consumption, high luminosity, high efficiency, long lifetime, and high materials stability. Since the properties of LEDs are highly dependent on the properties of phosphors, developing luminescent materials is essential. Ce-doped yttrium aluminum garnet (Y3Al5O12:Ce3+, YAG:Ce) is a widely used material in LEDs due to its excellent physical and optical properties. The emission of YAG:Ce phosphors can be tailored by the modification of chemical composition with foreign ions. With the substitution of Ga3+ ions on Al3+ sites on YAG:Ce, the emission peak shifts toward shorter wavelength, resulting in green emission. This blue-shift is attributed to the size of Ga3+ ions, which substitute for octahedrally coordinated Al3+ sites. The ionic radius of Ga3+ ion is larger than Al3+ ion, which causes the distortion of cubic symmetry of the phosphor. Consequently, the energy band gap between the lowest 5d and 4f states increases, leading the blue-shift of the emission peak. In this study, the Ga-substituted YAG:Ce (YAGG:Ce) green phosphors were synthesized by solid-state reaction and the effects of Al/Ga ratio on the photoluminescence properties of the phosphors were investigated. On the other hand, the stoichiometry of YAGG:Ce were controlled, showing that the luminance of the phosphors with nonstoichiometric composition is higher than that of the stoichiometric composition. |
| 저자 | 정하균1, 윤대호2, 최성호1, 우미혜1, 김지수1 |
| 소속 | 1한국화학(연), 2성균관대 |
| 키워드 | <P>YAGG:Ce; Stoichiometry; LEDs</P> |
