Discovery of orthorhombic perovskite oxides with low thermal conductivity by first-principles calculations

Orthorhombic perovskite oxides are studied by high-throughput first-principles calculations to explore new thermal barrier coating (TBC) materials with low thermal conductivities. The mechanical and thermal properties are predicted for 160 orthorhombic perovskite oxides. The average atomic volume is identified as a possible predictor of the thermal conductivity for the perovskite oxides, as it has a good correlation with the thermal conductivity. Five compounds, i.e., LaTmO3, LaErO3, LaHoO3, SrCeO3, and SrPrO3, having thermal conductivities under 1 W·m−1·K−1 and good damage tolerance, are proposed as novel TBC materials. The obtained data are expected to inspire the design of perovskite oxide-based TBC materials and also support their future functionality investigations.