Synthesis of YAG:Ce Phosphor via Different Aluminum Sources and Precipitation Processes.

Abstract

Luminescence D 6540Synthesis of YAG:Ce Phosphor via Different Aluminum Sources and Precipitation Processes. -Y3Al5O12:Ce 3+ phosphors are synthesized by four different precipitation processes using either Al(NO3)3 or NH4Al(SO4)2 as the aluminum source. A phase-pure phosphor is obtained by the normal strike precipitation process from Al(NO3)3 as aluminum source and NH4HCO3 as precipitation agent at 850°C. This sample has the highest emission intensity at 535 nm when excited at 470 nm. -(CHIANG*, C. C.; TSAI, M. S.; HSIAO, C. S.; HON, M. H.; J.

Red-Shifted Emission in Y3MgSiAl3O12:Ce3+ Garnet Phosphor for Blue Light-Pumped White Light-Emitting Diodes

“…When the lattice is distorted, the two excited energy levels can further split into five energy levels. 39,40 In Y 3−x MgSiAl 3 O 12 :xCe 3+ solid solutions, the substitution of Al 3+ (I) and Al 3+ (II) ions by Mg 2+ and Si 4+ ions enhances the lattice distortion, then the energy gaps between the five energy levels further increase. 41 The energy gap between the lowest excited-state level and the ground-state level decreases accordingly, leading to the shift of the emission spectrum to the lower-energy side, i.e., the red shift of the emission spectrum.…”

Fabrication of submicron-sized oxide phosphors and their spectroscopic properties

“…Only pressure-assisted techniques (Takamori and David, 1986;Hakuta et al, 2003;Li et al, 2004) allowed getting crystalline YAG at temperatures as low as 300.600 • C. Without the use of pressure a temperature of at least 700.1000 • C has to be applied to get crystalline YAG (Chiang et al, 2006). Hence, the molten salts synthesis is certainly extraordinary energy-efficient procedure.…”

Preparation of uniformly dispersed YAG ultrafine powders by co-precipitation method with SDS treatment

“…Recent studies showed, however, that starting with preformed YAG via liquidchemical synthesis methods rather than mixed aluminum and yttrium oxides was preferable for sintering transparent ceramics because solution-based techniques can achieve better chemical homogeneity [9]. Consequently, several liquid-chemical synthesis methods have been developed, such as co-precipitation [10][11][12][13], homogeneous precipitation [14,15], sol-gel processing [16][17][18][19], hydrothermal treatment [20], spray pyrolysis [21,22], combustion methods [23][24][25][26], etc. However, most of these approaches described so far suffer from timeconsuming procedures and/or complicated equipment or costly starting materials.…”