Synergistic Effects of Optical and Photoluminescence Properties, Charge Transfer, and Photocatalytic Activity in MgAl2O4:Ce and Mn-Codoped MgAl2O4:Ce Phosphors.

A gamma-ray irradiation-assisted polyacrylamide gel method has been used to synthesize MgAl₂O₄:Ce and Mn-codoped MgAl₂O₄:Ce phosphors. Ce ion doping improved the photoluminescence properties of MgAl₂O₄ but did not change the cubic spinel structure of the host. Transmission electron microscopy showed that the mean particle size of the Ce- and Mn-codoped MgAl₂O₄ nanoparticles was smaller than that of the MgAl₂O₄ nanoparticles. Ce and Mn codoping improved the light absorption capacity and utilization, the separation efficiency of photogenerated carriers, and the photocatalytic activity of the MgAl₂O₄ nanoparticles. The MgAl₂O₄:Ce:Mn nanoparticles exhibited high photocatalytic activity for photodegradation of methylene blue dye under simulated sunlight irradiation due to the synergistic effects of the band-edge position, the light absorption capacity and utilization, and the separation efficiency of photogenerated carriers. [ABSTRACT FROM AUTHOR]