Synthesis of YBCO superconductor by the method of combustion reaction in solution

Abstract

Solutions of metallic nitrate were prepared to obtain the Y 1 Ba 2 Cu 3 O 7-δ and Y 3 Ba 5 Cu 8 O 18-δ phases in different mixtures of urea and glycine balanced stoichiometrically according to the principle of propellant chemistry to be synthesized by the method of combustion reaction in solution using a thermal blanket type furnace. The obtained powders required a post-reaction heat treatment at 920° C for 2h in air. The X-ray diffraction (XRD) characterization showed that the synthesized powders have a predominant superconducting Y 1 Ba 2 Cu 3 O 7-δ phase with an orthorhombic crystal structure and a complementary phase Y 3 Ba 8 Cu 5 O 18-δ . The Y 3 Ba 5 Cu 8 O 18-δ phase was not found in any of the cases. The results of the transition electron microscopy (TEM) showed most grains with an average size of 300 nm and confirmed the Y123 phase. In addition, it was observed grains with an average diametrer of 1.6 m. The measurement of electrical transport gave a T c ∼ 91 K by the 4-probe method and by SQUID magnetometry it was obtained a T c ∼ 92 K for zero field cooled (ZFC) and field cooled (FC) magnetizations.