Yttria-stabilized zirconia with reduced thermal conductivity

A gas turbine engine component comprising:

• a superalloy substrate;
• a metallic bond coat on a surface of the substrate;
• and
• a thermal barrier coating having a columnar microstructure, the thermal barrier coating consisting essentially of zirconia partially stabilized by 1 to 3 weight percent yttria and to which is alloyed, in weight percent, one of the following additional metal oxides:
• 0.8 to 3.6% magnesia, 1.0 to 5.0% calcia, 1.9 to 8.8% strontia, 2.7 to 12.3% barium oxide, 1.4 to 6.5% nickel oxide, 2.8 to 12.8% ferric oxide, 1.4 to 6.5% cobaltous oxide, 2.5 to 11.3% scandium oxide, 5.8 to 22.5% lanthana, 5.7 to 23.0% neodymia, 6.0 to 24.3% gadolinium oxide, 6.3 to 24.8% dysprosia, and 1.0 to 30.0% ceria, the thermal barrier coating having a microstructure containing crystallographic defects formed by the additional metal oxide and that reduce the thermal conductivity of the thermal barrier coating.