Preparation and Characterization of Pyrochlore An₂Zr₂O₇（An=La, Nd） by Spray Pyrolysis

Zirconate pyrochlore (An₂Zr₂O₇) is a well known host material for actinide immobilization because of the chemical durability and radiation stability. Lanthanide (La, Nd) are surrogate elements for actinide that is widely used in experiments, pyrochlore structured La₂Zr₂O₇and Nd₂Zr₂O₇ are prepared at relative low temperature and short time via sol-spray pyrolysis method. X-ray diffraction (XRD), SEM and Raman are employed to investigate the structure characterization. Results show that the compositions are single pyrochlore phase; the Nd₂Zr₂O₇ pyrochlore drives structure phase transition from pyrochlore to defect fluorite. This synthetic method provides a potential pathway to immobilize high-level nuclear waste.