Effect of different annealing atmospheres on the structural and luminescence properties of Ce3+-doped YAG phosphors synthesized by sol–gel method

Cerium trivalent doped yttrium aluminum garnet (YAG:Ce3+) yellow phosphors have been successfully synthesized by sol–gel process and heat-treat at 900 °C for 2 h in different atmospheres such as vacuum, air and nitrogen gas. The objective of the present paper is to study the effects of annealing atmosphere on the structural, morphological and luminescence properties of YAG:0.5% Ce3+ powders. After elaboration, the samples were characterized by X-ray diffraction, field emission scanning electron microscopy (FESEM), Fourier transforms infrared spectroscopy (FTIR) and photoluminescence measurements. The XRD results confirmed the presence of single cubic phase for all samples independent of annealing atmosphere. FE-SEM micrograph results revealed that the particles present flake-like shapes. The YAG:Ce3+ phosphors showed broad green–yellow emission band in the range of 460–700 nm with maximum intensity at 530 nm assigned to the 5d → 4f transitions of Ce3+ ion. It is found that the annealing in vacuum atmosphere is the most suitable annealing condition for obtaining high quality YAG:Ce3+ powder with stronger emission intensity.