Trivalent Gadolinium-Doped Diopside (CaMgSi2O6) for Photoluminescence and EPR Investigation

Gd3+-doped CaMgSi2O6 phosphors with varying dopant content were processed successfully using sol-gel preparation. Prepared products were verified by x-ray diffraction data, which indicated the formation of a monoclinic phase. Scanning electron microscopy suggested the formation of tightly aggregated phosphor particles. A strong photoluminescence emission peak of 6P7/2 → 8S7/2 at 313 nm was observed in the studied phosphors under 273-nm excitation. The changes in emission intensity were also monitored with respect to the concentration of Gd3+. X-band electron paramagnetic resonance (EPR) spectra of the phosphors revealed the fine structure lines of Gd3+ ions typical of orthorhombic or lower symmetry. In addition, the intensity of the EPR spectrum from Gd3+ showed saturation beyond 0.03 mol of Gd3+ doping.