Novel phosphate glass ceramic of CaO-TiO2-P2O5 system containing Nd3+

For the first time, the CaO-TiO₂-P₂O₅ system was used to prepare phosphate glass ceramic doped with neodymium using the melt-quenching method at temperatures of 1350–1400 °C. Differential Thermal Analysis was used to investigate the thermal behavior of each glass sample, including the glass transition temperature (T_g), nucleation temperature (T_n), crystallization temperature (T_c), and onset of crystallization peak temperature (T_x). The Poulain and Hruby methods showed that increasing the neodymium content from 0.5 mol.% to 1.5 mol.% resulted in an 8 % decrease in glass stability and a 35 % increase in crystallization tendency. The type of crystallization also changed from surface to volume. Glass-ceramic samples were nucleated at 675 °C for 32 h, followed by growth at 795 °C and 830 °C for 6 h. XRD analysis identified crystalline phases Ca₃(PO₄)₂, and CaTi₄(PO₄)₆ at 795 °C and 830 °C. The crystal phases transformed from metaphosphate to NASICON. The crystal size was calculated and showed that neodymium caused a significant reduction in crystal size in glass-ceramics containing 0.5 mol% neodymium. FE-SEM micrographs of the prepared glass-ceramics confirmed the reduction in crystal size with the addition of neodymium oxide. Comparison of photoluminescence results for glass and glass-ceramics containing 0.5 mol.% Nd₂O₃ showed a decrease in emission intensity at 584 nm due to increased wave scattering from deposited phases.