Crystallization behavior, phase separation and fluorescence properties of lunar-soils-based glass-ceramics: Effects of Eu2O3

In this work, the dual effects of Eu 2 O 3 on crystallization behavior, phase separation and fluorescence properties in simulated-lunar-soils-based SiO 2 -MgO-CaO-Al 2 O 3 -K 2 O-TiO 2 -Na 2 O glass-ceramics (SMCA-Eu) were investigated and analyzed. It was demonstrated that as Eu 2 O 3 concentration increased, the crystallization activation energy of SMCA-Eu glass declined from 343.42 kJ/mol to 310.01 kJ/mol, subsequently rebounded to 318.43 kJ/mol. The Avrami parameter (n) exhibited distinctive surface crystallization of SMCA-Eu glass-ceramics system with crystalline phases of CaMgSi 2 O 6 , (Na,Ca)(Al,Si) 4 O 8 and Mg 2 Al 4 Si 5 O 18 . According to SEM and TEM results, the (Na,Ca)(Al,Si) 4 O 8 of SMCA-Eu glass-ceramics without Eu 2 O 3 transformed into CaAl 2 Si 2 O 8 and Mg 2 Al 4 Si 5 O 18 with increasing of Eu 2 O 3 content due to significant phase separation between Ca-rich and Si-rich regions. The optimal incorporation concentration was identified as 1 mol% Eu 2 O 3 , which yielded a fluorescence lifetime of 1.909 ms. Fluorescence intensity increased by a factor of 2.11 at 613 nm after crystallization, while significant phase separation in high-concentration Eu 3+ glass-ceramics enhanced fluorescence intensity despite limited crystallization. These findings indicated that SMCA-Eu glass-ceramics exhibit excellent red-blue light emission characteristics, making them promising candidates for plant growth lighting applications in lunar base environments.