Boosting the Ionic Conductivity in Sodium-Rich Antiperovskites Using Cluster Ions

Superionic conductors are vital to the development of all-solid-state batteries. Owing to the high abundance and low cost of sodium (Na), Na-based rechargeable batteries hold great potential for large-scale applications in the energy economy. However, only few superionic conductors of Na can reach the practically useful conductivity under ambient conditions. Here, by choosing cluster ions to form the Na-rich antiperovskites, we report large enhancement of the Na⁺ conductivity. In addition to uncovering the conduction mechanism, we have also studied other relevant physical properties of the proposed materials.