Self-oxidized NiO on cube-textured Ni for YBCO coated superconductor

In this paper, we report a self-oxidation approach to obtain NiO Oll the surface of Ni substrates. Under optimal oxidizing conditions, high-textured NiO layers on the surface of Ni substrates were obtained. Detailed pole figure (PF) measurements show an improvement in the full width at half maximum of NiO layers compared with that of Ni substrate. Orientation distribution function calculated from two PFs shows that the best cubic texture of NiO can be formed at 680 °C in 5 Pa oxygen. A grain size less than 1 μm is evident from scanning electron microscopy observation. Some possible ways were proposed to improve surface quality. The self-oxidation approach provides a potential to prepare high-J_c YBCO films on a large scale.