First principles material screening and trend discovery for the development of perovskite electrolytes for proton-conducting solid oxide fuel cells

Perovskite oxides are known for their ability to be modulated with elemental doping to tune desirable properties. Perovskites are used as proton-conducting ceramic (PCC) electrolytes for solid-oxide fuel cells. PCC electrolytes must have thermodynamic stability in both oxidizing and reducing environments, low electronic conductivity, and the ability to form protonic defects. To help discover PCC electrolyte materials and understand the role of different elements and compositions on material properties, high-throughput materials screening together with first-principles calculations can be utilized to scan a large elemental space. Here, we conduct a high-throughput scan of 4793 materials to determine how different cation species modulate stability, electronic conductivity, and defect formation. Our filtering analysis identifies 116 materials that are electronically inactive and stable under reducing and oxidizing conditions. Furthermore, we identify 43 materials that are also stable under a pure CO2 2 environment. For all 116 materials, we conducted an analysis of material stability under sintering conditions and an analysis of oxygen vacancy and protonic defect formation to identify trends in ionic conductivity. This study provides a supplemental understanding of the role of elemental identity and doping ratios on material stability and activity that can aid in the design of perovskite oxides for proton-conducting applications.