NASICON类固溶体的形成和稳定

用固相反应法合成了NASICON固溶体Na~1~+~2Zr~2~-~xM~x(PO~4)~3(M=Y、Yb或In)。测定了晶胞参数随着取代量x的变化, 并从结构和结晶化学的角度进行解释。用三价离子Y^3^+、Yb^3^+、In^3^+或二价离子Mg^2^+作为结晶化学稳定剂取代Na~3Zr~2Si~2PO~1~2中的Zr^4^+离子能生成固溶体, 并把NASICON的高温三方相(空间群R3c)稳定在室温, 阻止了在150℃左右时单斜三方的相转变。总结了高温相稳定在低温的条件。

Formation and stability of NASICON solid solution

Nasicon solid solution Na1+xZr2-xMx(PO4)3 (M = Y, Yb, or In) was prepared by solid-state reaction. The change of lattice parameter with changing x was determine and explained from the point of view of crystal chem. Nasicon solid solution can also be for prepared by the substitution of trivalent ions (Y3+, Yb3+, In3+) or bivalent Mg2+ for Zr4+ ion in Na3Zr2Si2PO12. At the same time, the high-temp. rhombohedral phase (space group R3c) is stabilized at room temperature Therefore, the monoclinic J rhombohedral phase transition at ~150?disappears. The condition of stabilizing the high-temp. phase is discussed.