Un-doped and ZnAlxO1.5x+1:0.1 mol% Tb3+ (ZAOT) nano-powders were synthesized via citrate sol-gel method. The Alx moles were varied in the range of 0.25 ≤ x ≤ 5.0. The X-ray powder diffraction (XRD) data reveal that for x < 1.5, the prepared samples crystal structure consists of mixed phases of the cubic ZnAl2O4 and hexagonal ZnO phases, while for x ≥ 1.5 the structure consists of single phase of cubic ZnAl2O4. The Raman and Fourier-transform infrared (FTIR) vibrational spectroscopy show the presence of vibrations emanating ZnAl2O4 spinel. Scanning electron microscopy (SEM) and transmission electron microscopy (TEM) show the presence of irregular sphere at x ≥ 2.0 attributed to ZnAl2O4. The photoluminescence (PL) spectroscopy reveals emissions from both the host and Tb3+ transitions. Emissions from Tb3+ are observed at 382, 414, 439, 458 nm and 489, 545, 585, 621 nm, which were attributed to the 5D3 → 7F6,5,4,2 and 5D4 → 7F6,5,4,3, respectively. The results confirm that the Tb3+ occupation site depends on the Alx moles. The International Commission on Illumination (CIE) colour chromaticity shows that the emission colour can be tuned from blue to green by varying the Alx moles.
|Number of pages||7|
|Journal||Journal of Rare Earths|
|Publication status||Published - Mar 2023|
- Al moles
- Citrate sol–gel
- Rare earths