Use of Eggshell Waste as a Source of CaO in Sm3+-Doped Na2O-B2O3-CaO-SiO2 Glass Preparation

In this research, calcium carbonate from eggshell waste was used to prepare the soda-lime borosilicate glass samples (Na₂O-B₂O₃-CaO-SiO₂) doped with samarium ions (Sm³⁺) at different Sm₂O₃ concentrations (0, 0.1, 0.2, 0.3, 0.4 and 0.5 mol%). A conventional melt-quenching method at 1,100°C for 3 h was applied in this work to produce the glass samples. The samples were then characterized by XRD, DTA, FT-IR, UV-Vis spectrophotometer and PL techniques. The results showed that the obtained glasses had amorphous structure, and the glass density tended to increase with the addition of Sm₂O₃. The FTIR spectra of the main glass structure revealed that it was composed of trigonal BO₃ and tetrahedral BO₄ borate groups mixing with SiO₄ tetrahedra and non-bridging oxygen. The addition of samarium ions to the glass resulted in a strong orange emission at 562 nm (⁴G_5/2→⁶H_5/2), 600 nm (⁴G_5/2→⁶H_7/2), 646 nm (⁴G_5/2→⁶H_9/2) and 708 nm (⁴G_5/2→⁶H_11/2) under excitation at 403 nm. The results confirmed that 0.3 mol% Sm₂O₃-doped glass exhibited the highest emission intensity, which suggested that eggshells have a high potential to be used as an alternative  CaCO₃-raw material in the production of an efficient luminescent and environmentally-friendly optical electronics material.

Keywords: soda-lime borosilicate glass; waste; eggshell; waste utilization; luminescence

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