Ion conductors of light alkaline metals based on earth‐abundant elements are important components for all‐solid‐state batteries. The new sodium‐rich phosphidosilicate Na2SiP2 was synthesized by solid state reaction of stoichiometric amounts of the elements at 973 K and characterized by single‐crystal X‐ray diffraction (space group Pccn (no. 56), a = 12.7929(5) A, b = 22.3109(9) A, c = 6.0522(2) A and Z = 16) and solid‐state NMR under MAS conditions. The compound forms dark‐red twinned crystals, and its crystal structure contains edge‐sharing SiP4 tetrahedra connected to infinite ∞1[SiP4/2] chains. The sodium ions between the chains are fairly mobile. Electrochemical impedance spectroscopy shows a total ionic conductivity of σ(Na+, 373 K) = 2.3 ? 10–6 Scm–1 with an activation energy of Ea = 0.43 eV, and the galvanostatic polarization reveals mixed conduction behavior with a transference number of 0.8.

中文翻译：

---

磷硅酸钠 Na2SiP2 的合成与结构

基于地球丰富元素的轻碱金属离子导体是全固态电池的重要组成部分。新的富钠磷硅酸盐 Na2SiP2 是通过化学计量的元素在 973 K 的固态反应合成的，并通过单晶 X 射线衍射（空间群 Pccn (no. 56), a = 12.7929(5) A, b = 22.3109(9) A, c = 6.0522(2) A 和 Z = 16) 和 MAS 条件下的固态 NMR。该化合物形成深红色孪晶，其晶体结构包含连接到无限∞1[SiP4/2]链的共享边缘的SiP4四面体。链之间的钠离子是相当流动的。电化学阻抗谱显示总离子电导率为 σ(Na+, 373 K) = 2.3 ? 10–6 Scm–1，活化能为 Ea = 0.43 eV，