Effects of gold on YBa2Cu3O7−x at elevated temperatures

The interaction between Au and YBa2Cu3O7−x from 800 to 878 °C in 1 atm O2 was studied. Over this temperature range, Cu and small amounts of Ba were removed from the 123 leaving 211 and presumably BaCuO2. CuO crystals were present on the Au surface after the experiments. For 4-h anneals Cu diffused primarily along the surface of the Au and through Au grain boundaries. Under the same conditions, Cu was also removed from DyBa2Cu3O7−x forming CuO crystals on the Au surface.