Synthesis of Antiperovskite Solid Electrolytes: Comparing Li<sub>3</sub>SI, Na<sub>3</sub>SI, and Ag<sub>3</sub>SI
Liang Yin, Megan Murphy, Kwangnam Kim, Linhua Hu, Jordi Cabana, Donald J. Siegel, Saul H. Lapidus
Abstract
Prior calculations have predicted that chalcohalide antiperovskites may exhibit enhanced ionic mobility compared to oxyhalide antiperovskites as solid-state electrolytes. Here, the synthesis of Ag-, Li-, and Na-based chalcohalide antiperovskites is investigated using first-principles calculations and in situ synchrotron X-ray diffraction. These techniques demonstrate that the formation of Ag3SI is facilitated by the adoption of a common body centered cubic packing of S2– and I– in the reactants and products at elevated temperatures, with additional stabilization achieved by the formation of a solid solution of the anions. The absence of these two features appears to hinder the formation of the analogous Li and Na antiperovskites.