Temperature-dependent characteristics of ZnO phosphors from synchrotron-based vacuum ultraviolet photoluminescence spectroscopy

We report the temperature-dependent emission characteristics of ZnO phosphors in the range of 10 to 300 K measured using the synchrotron-based vacuum ultraviolet (VUV) photoluminescence spectroscopy. The ZnO phosphors with different morphologies: pyramid-like and sheet-like synthesized via co-precipitation and solid-state reaction methods, respectively and reveal various defect emission bands in the UV-Vis-NIR region. In the ZnO phosphor having the sheet-like morphology, the CIE coordinates shift closer to the pure white region and the emission intensity decreases rapidly with the increase in the temperature. This is due to the strong electron–phonon interactions that level up the thermally active non-radiative recombination processes. These phosphors exhibit high thermal stability with acceptable Color Rendering Index and color quality scale values and are thus suitable for space applications spanning from detection to the utilization of VUV radiations.