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It is demonstrated that electrodeposition is a promising cost-effective technique to grow oxide buffer on metallic tapes. The resultant layer of CeO2 shows the biaxial texture of FWHM = 5.5° as well as a smooth surface of RMS = 2.0 nm, and YBa2Cu3O7−δ coated conductor with such a buffer exhibits the critical current density of 1.85 MA cm−2 at 77 K. Of more interest is that the CeO2 film thickness reaches a high value of more than 200 nm without any cracks, while it is very hard to achieve a thickness of more than 70 nm in the conventional vapor deposition methods employed. [ABSTRACT FROM AUTHOR]

Comparing with conventional physical vapor deposition methods, electrochemistry deposition technique shows a crack suppression effect by which the thickness of CeO 2 films on Ni–5 at.%W substrate can reach a high value up to 200 nm without any cracks, make it a potential single buffer layer for coated conductor. In the present work, the processes of CeO 2 film deposited by electrochemistry method are detailed investigated. A hydroxide reactive mechanism and an oxide reactive mechanism are distinguished for dimethyl sulfoxide and aqueous solution, respectively. Before heat treatment to achieve the required bi-axial texture performance of buffer layers, the precursor CeO 2 films are identified in nanometer scales. The crack suppression for electrochemistry deposited CeO 2 films is believed to be attributed to the nano-effects of the precursors. [ABSTRACT FROM AUTHOR]

Bilayer buffer architecture of Gd 2 Zr 2 O 7 (GZO)/Y 2 O 3 was prepared on the biaxially textured tape of Ni–5 at% W (NiW) by reactive sputtering deposition technique. The buffer layer of GZO films were deposited with different thicknesses on Y 2 O 3 seeding layer with a given thickness of 20 nm. According to the results of φ-scan, the in-plane FWHMs of GZO films decreased and then reversed with increasing thickness of GZO, which corresponded with the in-plane FWHMs and superconducting properties of YBa 2 Cu 3 O 7− δ (YBCO) films. Reflection High-Energy Electron Diffraction (RHEED) was carried out to examine the surface texture of GZO films and the deteriorated surface alignment was found for thicker films. The thickness effect of GZO on performance of YBCO is the coupling result of surface texture and blocking effect caused by thickness. With the balance of these two factors, the YBCO/GZO(120 nm)/Y 2 O 3 /NiW architecture exhibit relatively high performance with the transition temperature T c of 92 K, a transition width Δ T c below 1 K, and a critical current density J c of 0.65 MA/cm 2 . [ABSTRACT FROM AUTHOR]