Improving superconducting properties of YBCO high temperature superconductor by Graphene Oxide doping

In this research, we report the synthesis and characterization of YBa2Cu3O7-δ (YBCO) high temperature superconductor prepared by sol-gel method and doped with Graphene Oxide (GO) in different weight percentages, 0, 0.1, 0.7 and 1 % wt. The x-ray diffraction (XRD) analysis confirms the formation of orthorhombic phase of superconductivity for all the prepared samples. We found that GO doping reduces the crystalline size of the samples. We evaluated the effects of GO doping on the normal state resistivity (ρ), superconducting transition temperature (Tc) and critical current density (Jc). The results show that the GO doping has a positive effect on these properties. Also, the highest Jc is obtained for the 0.7 %wt GO doped YBCO compound that its critical current density is about 15 times more than the Jc of pure one in 0.4 T magnetic field. The scanning electron microscope (SEM) analysis shows that there are better connections between the grains of GO doped samples. •Graphene Oxide doping increased the YBCO critical current density.•Graphene Oxide creates a better connection between the YBCO grains.•The normal resistivity of samples were decreased by GO doping to YBCO compounds.•Graphene Oxide doping has a positive effect on the critical transition temperature.