Variation of Structure and Photoluminescence Properties of Ce(3+) Doped MgAlON Transparent Ceramics with Different Doping Content

Transparent MgAlON:Ce fluorescent ceramics with doping content of 0.005, 0.01, and 0.02 at % were fabricated by pressureless sintering. All the samples were dense and large in grain size. Under the excitation of 320 nm UV, the samples emitted blue lights centered around 410 nm. The 0.005 and 0.01 at % Ce(3+) doped samples were single phase by XRD detection, and possessed good optical and mechanical properties, and luminous thermal stability. The fluorescence lifetime, the CL and PL spectra analysis, indicated that most of the luminous centers were segregated in GB, and there was still a small part of second phase existing in 0.01 at % Ce(3+) doped sample, which revealed that spectroscopy methods possessed better sensitivity in smaller scale and lower concentration detection than XRD. As the doping content increasing to 0.02 at %, a mass of second phase arose, which resulted in the optical transparency, mechanical property, luminous thermal stability decline, and the PL spectra red shift by the formation of second phase. It revealed that the performances were fatally deteriorated by excess doping of Ce(3+) ions.