Synthesis and luminescence study of Eu -doped SrYAl O phosphor.

Rare-earth ions play an important role in eco-friendly solid-state lighting for the lighting industry. In the present study we were interested in Eu ion-doped inorganic phosphors for near ultraviolet (UV) excited light-emitting diode (LED) applications. Eu ion-activated SrYAl O phosphors were prepared using a solution combustion route at 550°C. Photoluminescence characterization of SrYAl O :Eu phosphors showed a 612 nm emission peak in the red region of the spectrum due to the D → F transition of Eu ions under excitation at 395 nm in the near-UV region and at the 466 nm blue excitation wavelength. These red and blue emissions are supported for white light generation for LED lighting. Structure, bonding between each element of the sample and morphology of the sample were analysed using X-ray diffraction (XRD) and scanning electron microscopy (SEM), which showed that the samples were crystallized in a well known structure. The phosphor was irradiated with a Co-γ (gamma) source at a dose rate of 7.2 kGy/h. Thermoluminescence (TL) studies of these Eu -doped SrYAl O phosphors were performed using a Nucleonix TL 1009I TL reader. Trapping parameters of this phosphor such as activation energy (E), order of kinetics (b) and frequency factor (s) were calculated using Chen's peak shape method, the initial rise method and Ilich's method.