Transmission electron microscope study on electrodeposited Gd2O3 and Gd2Zr2O7 buffer layers for YBa2Cu3O7−δ superconductors

We have investigated the microstructures of electrodeposited Gd2O3 (GO) and Gd2Zr2O7 (GZO) buffer layers for YBa2Cu3O7−δ (YBCO) superconductors with conventional transmission electron microscopy (TEM). A high density of nanoscale voids was present in the GZO buffer layers. No voids were observed in GO buffer layers grown on GZO. YBCO superconductor grown on the GO/GZO buffer layer structure produced a critical current density (Jc) of 3.3 × 106 A/cm2 at 77 K in zero field.