Gd2O3-Nd2O3-ZrO2-CeO2体系的高温固相反应研究

为研究Gd₂O₃-Nd₂O₃-ZrO₂-CeO₂四元氧化物体系的高温固相反应，以Gd₂O₃、Nd₂O₃、ZrO₂、CeO₂混合粉体为原材料，在1 673 K和1 773 K温度下煅烧24、48、72 h，分别制备了系列样品，并对合成样品进行了XRD和SEM分析。结果表明，合成产物为具有缺陷萤石相且伴有少量烧绿石相的Gd_2-xNd_xZr_2-xCe_xO₇（0≤x≤2）晶体化合物。随着煅烧温度的升高和煅烧时间的延长，产物中立方烧绿石相的化合物增多，晶粒尺寸变大，且有少量未知相生成。进而探讨了锆基陶瓷固化多核素的潜在应用，并提出了未来研究的相关热点问题。

Solid-solid Reaction ofGd2O3-Nd2O3-ZrO2-CeO2 System at High Temperature

To investigate solid-solid reactions of Gd₂O₃-Nd₂O₃-ZrO₂-CeO₂ quaternary oxide system at high temperature conditions, using the mixed powders of Gd₂O₃, Nd₂O₃, ZrO₂ and CeO₂ as raw materials, a series of samples were prepared at the calcinations temperature of 1 673 K or 1 773 K in duration time of 24, 48 and 72 h, respectively. By analysis of XRD and SEM for the as-gained samples, the results indicate that Gd_2-xNd_xZr_2-xCe_xO₇ (0≤x≤2) crystalline compounds are synthesized, which possess oxygen-deficient fluorite phase companying with minor pyrochlore phase. As the rising of calcination temperature and/or the extending of calcination time, more pyrochlore phase and larger grain size and minor unknown phase are observed in the as-synthesized samples. Finally, the potential applications of zircon-based ceramic waste forms loading multi-nuclide were discussed and the related hotspot issues in future were presented as well.