Manufacture of $\hbox {GdBa}_{2}\hbox {Cu}_{3}\hbox {O}_{7 - x}$ Superconducting Thin Films Using High-Thermal-Stability Precursors Playing the Role of Intermediate-Phase G

We have developed a fluorine-free metal-organic decomposition method using acrylic acid as the solvent for the synthesis of GdBCO superconducting thin films. Commonly used propionic acid was also used to make a comparison with acrylic acid. Acrylic acid was found to be polymerized during drying, resulting in high thermal stability of the precursor solution. Due to the elevated decomposition temperature of the organic compounds in the acrylic-acid-based precursor, the formation of intermediate phases such as CuO was found delayed; therefore, the grain growth and phase segregation were suppressed. The superior quality of pyrolyzed films induced by the use of polymerizable acrylic acid is reflected in the J_c of the GdBCO films, which achieved 1.2MA/ cm².