Fast cationic conduction is necessary for a number of solid-state technologies and is particularly critical for solid-state batteries as solid electrolytes are typically poor conductors. This article illustrates the concept of low-dimensional networked (low-DN) anti-perovskite via first-principles computations and shows that superionicity (i.e. the conductivity is above 1 mS cm^-1 at room temperature) can be achieved by lowering the dimensionality of the connected octahedra of the anti-perovskite. In particular, we use the Li-O-Cl model system and study the diffusion of Li in 3DN-Li₃OCl, 2DN-Li₄OCl₂, 1DN-Li₅OCl₃, and 0DN-Li₆OCl₄. We find that the lower the dimensionality, the lower the Li migration barriers and the higher the diffusion coefficients are. We attribute this improved ionic conduction to the decreased size of the bottlenecks and the softening of the rotation modes of the octahedra in the structure. To further explore the concept of low-DN anti-perovskites, we screen 256 model materials in the I-VI-VII group chemical space by computing the phase stability and bandgap of 3DN-X₃BA, 2DN-X₄BA₂, 1DN-X₅BA₃, and 0DN-X₆BA₄ (X= Li, Na, K, Rb; B=O, S, Se, Te; and A=F, Cl, Br, I). The calculations suggest that 20% of the structures might be synthesized and a number of them possess reasonable cationic migration barriers (<400 meV). This study puts forward a new principle for designing solid superionic conductors by lowering the dimensionality of the primitive structural units.

快速阳离子传导对于许多固态技术都是必需的，并且对于固态电池尤为重要，因为固态电解质通常是不良导体。本文通过第一性原理计算说明了低维网络化（低DN）钙钛矿的概念，并表明可以通过降低金属离子的尺寸来实现超离子性（即，室温下电导率高于1 mS cm ^-1）。反钙钛矿的相连八面体。特别地，我们使用锂OCL模型系统和研究Li的3DN锂扩散₃ OCL，2DN锂₄ OCL ₂，1DN利₅ OCL ₃，和0DN锂₆ OCL₄。我们发现，尺寸越低，Li迁移势垒越低，扩散系数越高。我们将这种改善的离子传导归因于瓶颈尺寸的减小和结构中八面体旋转模式的软化。为了进一步探索低DN抗钙钛矿的概念，我们通过计算3DN-X ₃ BA，2DN-X ₄ BA ₂和1DN的相稳定性和带隙来筛选I-VI-VII组化学空间中的256种模型材料-X ₅ BA ₃和0DN-X ₆ BA ₄（X ＝ Li，Na，K，Rb； B ＝ O，S，Se，Te；以及A ＝ F，Cl，Br，I）。计算表明，可能合成了20％的结构，其中许多具有合理的阳离子迁移势垒（<400 meV）。这项研究提出了一种通过降低原始结构单元的尺寸来设计固体超离子导体的新原理。