Aqueous chemical solution deposition of lanthanum zirconate and related lattice-matched single buffer layers suitable for YBCO coated conductors: A review

The main focus of this review article is to present an overview of the present status of the water-based buffer layers for YBa2Cu3O7−x coated conductors. In the present time, the development of second generation superconducting YBa2Cu3O7−x coated on flexible substrates are attractive for the researchers around the world due to their possible application potential in long distance electric power transmission systems and for high magnetic field applications. For this to be realized, buffer layers are required. They play an important role for the protection of the YBa2Cu3O7−x layer coated on top of the flexible substrates. However, people are interested to find an improvement in the buffer layer materials that has the most suitability for the YBa2Cu3O7−x superconductors, using low-cost manufacturing processes. In accordance to this, chemical solution deposition is a method that can offer a solution for this problem. This deposition method is highly versatile and cost-effective technique for fabricating buffer layers and YBa2Cu3O7−x coated conductors for high performance applications. In effect to that, aqueous methods can additionally offer cost-effective and environmentally-friendly solution. In the following work, the preparation and characterization of buffer layers including that of lanthanum zirconate, lanthanum doped cerium oxide, lattice tuned cerium doped lanthanum zirconate films and non-stoichiometric lanthanum zirconate buffer layers on metallic Ni-5%W substrates using chemical solution deposition (CSD), starting from aqueous precursor solutions is discussed in detail. Their performance in terms of crystallinity, buffer layer action is presented.