论文部分内容阅读
Red phosphors, Li2Sr0.996 Si O4: Pr3+0.004, with different hydrothermal conditions were prepared via hydrothermal synthesis and then heat-treatment. The chemical structures of the phosphors were identified with X-ray diffraction(XRD). Surface morphological features were observed by scanning electron microscopic(SEM) investigation. Spectra of excitation and emission for the phosphors were also obtained by a spectrophotometer. Results showed that the optimum conditions were as follows: p H value of solution was 1–2, reaction temperature was at 180 oC for 24 h. The as-prepared phosphors exhibited two excitation dominant peaks at 451 and 486 nm, attributed to transitions of 3H4→3P2 and 3H4→3P0 of Pr3+, respectively. A narrow emission peak at 610 nm corresponded to the energy level transition of 3P0→3H6 of Pr3+ under excitation of light at 451 nm, which indicated promising candidate red phosphors for blue LED chips.
Red phosphors, Li2Sr0.996SiO4: Pr3 + 0.004, with different hydrothermal conditions were prepared via hydrothermal synthesis and then heat-treatment. The chemical structures of the phosphors were identified with X-ray diffraction (XRD) Spectra of excitation and emission for the phosphors were also obtained by a spectrophotometer. Results showed that the optimum conditions were as follows: p H value of solution was 1-2, reaction temperature was at 180 oC for 24 h. The as-prepared phosphors exhibited two excitation dominant peaks at 451 and 486 nm, attributed to transitions of 3H4 → 3P2 and 3H4 → 3P0 of Pr3 +, respectively. A narrow emission peak at 610 nm corresponded to the energy level transition of 3P0 → 3H6 of Pr3 + under excitation of light at 451 nm, which indicates promising candidate red phosphors for blue LED chips.