掺杂NASICON系统的23Na NMR研究

化合物Na3Zr2Si2PO12。是由ZrO6八面体与SiO4或PO4四面体共角构成的开放三维骨架结构，Na 位于骨架间隙，称之为NASICON（NaSuperIoaicConductor），具有和Na－Al2O3相似的离子电导率（在300℃时，σ＝0．2Ω－1·cm-1［1］但是由于该化合物在100－2000℃间存在单斜一、立方的可逆相变，使其应用受到限制．为了抑制这种相变，已进行了骨架掺杂的研究工作，制备出了多种化学掺杂的NASICON系统［2］．在Na3Zr2Si2PO12化合物中，三个Na十分别位于结构中两个不同的位置，然而掺杂以后，骨架结构发生变化，这时Na十位置，将关系…

~(23)Na NMR Study on the Doped NASICON System

The sodium positions in the doped NASICON solld solution Na3Zr2-xYxSi2-x .P1 xO12 system were investigated by using 23Na NMR techniques. The results of NMR indicats that the surroundings of the sodium cations in compounds with different compositions are different because the network structures are disordered by replacement of Y3 for Zr4 ions in the crystal structure. While the composition x is small, the sodiam cations locate at two sites, Na(1) and Na(2) sites, in the structure. With x increasing,the surroundings of the sodium cations change and the position of the sodium cations is of only one kind at x=1.2. These results are important for understanding the crystal rule and the effect of the doped cation on the surroundings of the sodium cations in Na3Zr2-xYxSi2-xP1 xO12 solid state solution system.