Synthesis and characterization of Eu3Ba5Cu8O18-δ superconductor doped with 0.1% Graphene oxide

This research presents the synthesis and evaluation of the structural and morphological properties of superconducting Eu3Ba5Cu8O18-δ doped with 0.1% graphene oxide, using the solid state reaction method. The structural analysis performed on the samples, both doped and undoped, allowed identifying the main phase as Eu3Ba5Cu8O18-δ (Eu358), with orthorhombic structure and space group Pmm2(25), maintaining superconducting properties in both cases. In addition, it was observed that doping with graphene oxide resulted in the formation of a minority phase of EuBa4Cu3O9 (Eu143), with cubic structure and space group P23(195). As for the morphological characterization, it was evidenced that the undoped sample presents aggregates formed by non-uniform size grains, with an average size of approximately 97 µm. In contrast, the sample doped with 0.1% graphene oxide exhibits significant improvements in uniformity and grain boundaries, with an average size of about 141 µm. These results confirm obtaining Eu3Ba5Cu8O18-δ with a 73% superconducting phase, exceeding the percentages previously reported using the solid-state reaction method.