Effect of Nd2O3 and CeO2 co-doping on phase and microstructure evolutions of ZrSiO4-based borosilicate glass-ceramics

Developing new matrices capable of simultaneous immobilization of lanthanides and actinides are challenging. Herein, this paper reported the ZrSiO 4 -based borosilicate glass-ceramics with excellent immobilization capabilities of lanthanides and actinides. The phase evolution and microstructure transformation affected by the (Nd, Ce)-co-doping content were investigated systematically. The results indicated that the solubility limits of Nd and Ce in the obtained glass-ceramics decreased with increasing temperature, which were up to 18, 16 and 10 at% at 1400 °C, 1450 °C and 1500 °C, respectively. The formation rate of ZrSiO 4 increased with the increase of the (Nd, Ce)-co-doping content and temperature, which reached the highest value of 96.43 wt% with Nd and Ce content of 10 at% at 1500 °C. The densification of the obtained glass-ceramics also increased with the increase of the content of Nd and Ce. In addition, it was found that the immobilization mechanism of the resulting glass-ceramics was the synergistic immobilization effect of the ceramic crystal and glass network. This work indicated that the ZrSiO 4 -based borosilicate glass-ceramics might be promising matrices for immobilizing high-level radioactive wastes containing lanthanides and actinides.