Korean Journal of Materials Research ISSN:1225-0562(Print) 2287-7258(Online) 한국재료학회지

BaSiO₃:RE³⁺ (RE = Sm or Eu) phosphor powders with different concentrations of activator ions are synthesized using the solid-state reaction method. The effects of the concentration of activator ions on the structural, photoluminescent, and morphological properties of the barium silicate phosphors are investigated. X-ray diffraction data reveals that the crystal structure of all the phosphors, regardless of the type and the concentration of the activator ions, is an orthorhombic system with a main (111) diffraction peak. The grain particles agglomerate together to form larger clusters with increasing concentrations of activator ions. The emission spectra of the Sm³⁺-doped BaSiO₃ phosphors under excitation at 406 nm consist of an intense orange band at 604 nm and three weak bands centered at 567, 651, and 711 nm, respectively. As the concentration of Sm³⁺ increases from 1 to 5 mol%, the intensities of all the emission bands gradually increase, reach maxima at 5 mol% of Sm³⁺ ions, and then decrease significantly with further increases in the Sm³⁺ concentration due to the concentration quenching phenomenon. For the Eu³⁺-doped BaSiO₃ phosphors, a strong red emission band at 621 nm and several weak bands are observed. The optimal orange and red light emissions of the BaSiO₃ phosphors are obtained when the concentrations of Sm³⁺ and Eu³⁺ ions are 5 mol% and 15 mol%, respectively.