Physico-mechanical and photoluminescence properties of EuxMg2?xSiO4 system sintered under different conditions

This work focuses on sintering of Eu_xMg_2?xSiO₄ (x = 0.0, 0.01, 0.03, 0.05) forsterite ceramics under different conditions and study their microstructures, physico-mechanical and photoluminescence characteristics. The starting materials were waste silica fume, pure MgO and europium oxide (Eu₂O₃). The prepared batches were sintered up to 1500 °C in the presence or absence of carbon in ambient atmosphere. The presence of carbon helped in reduction of Eu³⁺ into Eu²⁺. The effect of sintering conditions and formed phases on the properties of final product were investigated. The results indicated that the specimens sintered without carbon exhibited improved physico-mechanical properties with formation of forsterite and Eu_4.67 (SiO₄)₃O precipitated from the formed liquid phase. While the samples sintered in carbon exhibited lower physic-mechanical properties with formation of forsterite and clinoenstatite. Photoluminescence properties were improved with increasing the amount of added Eu₂O₃ for all sintered samples. The specimens sintered without carbon exhibited life time higher than those sintered in the presence of carbon.