A method for manufacturing a coating includes dissolving at least one salt in a mixture of water and ethanol to form a precursor solution, adding an additive to the precursor solution to form a fuel solution, and injecting the fuel solution into a plasma flame. The additive includes at least one of urea or ammonium acetate. The additive functions as a fuel to increase a temperature of the plasma flame. The method further includes manufacturing the coating on a substrate. The coating includes a garnet structure including a predetermined amount of yttrium-aluminum, one or more first cracks extending completely through a thickness of the coating, and a porosity greater than ten volume percent.