Photoluminescence properties of (Y1−xCex)3Al5O12 (x = 0.005–0.03) nanophosphors and transparent ceramic by a homogeneous co-precipitation method

Fine and dispersed (Y1−xCex)3Al5O12 (x = 0.005–0.03) nanophosphors were co-precipitated uniformly using a homogeneous co-precipitation process. With an excitation wavelength λex of 455 nm, the YAG:Ce phosphors showed strong luminescence with maxima at 550 nm in the range of 475–650 nm. The emission intensity becomes stronger due to the improved crystallinity and decreased surface defects of the resultant phosphors with increasing calcination temperatures. The quenching concentration of Ce3+ was 1.5 at% and the quenching mechanism was Ce–Ce interactions and lattice defects. The fluorescence lifetime of the phosphors decreased with increasing Ce concentrations and temperatures. The mechanism is influenced by defects both in surface and body. The resultant YAG:Ce powders showed an excellent sintering activity and can be sintered into transparent ceramic under vacuum technique. Compared with the phosphors, the transparent ceramic exhibits stronger luminescence properties and shorter fluorescence lifetime.