Calcium Doping Effect On Structural and Optical Properties of Zn2SiO4 Phosphor Material

Phosphor materials present a distinct family of compounds that were discovered decades ago. Phosphors have the ability to emit light even after the excitation light source is removed. Consequently, various applications have arisen, such as screen displays and LED lamps. In this context, we propose in the current study to investigate the physical properties of silica-zinc silicate (SiO 2 /Zn 2 SiO 4 ) phosphor ceramic composite obtained through a three-step sol–gel synthesis process. Then, the impact of calcium (4 at. %) doping was examined. XRD and TEM analysis prove the successful formation of a mixed phase with silica being the dominant, while zinc silicate, alongside traces of zinc oxide, is observed as well. FTIR and Raman come to support these outcomes and reveal the fingerprint peaks of the lattice. Moreover, UV–Vis analysis reveals that calcium doping seems to reduce the bandgap value (5.52 to 5.36 eV) due to the formation of a band tail. More importantly, the calcium induces a clear impact on the photoluminescence emission curve. The NBOHC defect is the most common emission centre in silica-based systems that is detected through EPR technique. Such defects emission shift from 773 to 755 nm after calcium doping. The outcomes of this study are promising and show for the first time the effect of alkaline earth elements single doping on the structural and photoluminescence characteristics of zinc silicate lattice.