An extensive experimental study of trivalent iron (Fe3+) ions in orthorhombic lithium gallate nanocrystals was undertaken. Various spectroscopic methods, such as Raman spectroscopy, extended X-ray absorption fine structure, the Mössbauer effect, electron paramagnetic resonance, photoluminescence, thermoluminescence, and cathodoluminescence were used to investigate the synthesized phosphor. This study revealed the existence of multiple Fe3+ sites, out of which the tetrahedral sites are preferentially occupied. Extensive optical studies showed that the Fe3+ doped lithium gallate phosphor is a promising candidate for various luminescence and thermoluminescence-related applications in the near-infrared regime.
Keywords: gallates; iron doping; luminescence; multisites.