Photoluminescence investigations of Zn2SiO4 co-doped with Eu and Tb ions

Zinc silicate phosphors co-doped with Eu³⁺ ions and also with both Eu³⁺ and Tb³⁺ ions were prepared by high temperature solid state reaction in air or reducing atmosphere. The luminescence characteristics of the prepared phosphors were investigated. While in the samples prepared in air, Eu³⁺ emission was found to be dominant over Tb³⁺ emission, in the samples prepared in reducing atmosphere, intense Eu²⁺ emission at 448 nm was found to be predominant over narrow Tb³⁺ emission. Luminescence studies showed that Eu³⁺ ions occupy asymmetric sites in Zn₂SiO₄ lattice. The intense f-f absorption peak of Eu³⁺ at 395 nm observed in these phosphors suggests their potential as red emitting phosphors for near ultra-violet light emitting diodes.