Investigation of Sm substitution on structural and superconducting properties of Y1Ba2−xSmxCu3O7−δ superconductors

Highlights: • YBSCO superconducting samples were prepared with the X-values 0.0, 0.01, 0.03, 0.05 by solid state reaction. • The transition temperature of superconductivity was investigated by the R–T measurement method. It was found that the composition has a superconducting transition. • The superconducting transition temperature decreases by increasing Sm, and in contrast, increases the special electrical resistance and the transitional width. • X-ray diffraction measurements showed that the Sm substitution at the Ba site in $Y_{1}B{a}_{2}C{u}_3{O}_{7-\delta }$(Y−123) confirms the formation of the 123 phase and specifies that all samples are orthorhombic with the Pmmm space. • It was determined from SEM images that by increasing the Sm the size of the grain decrease, and increases the porosity in the samples. Weakness of inter-grain connections can predict that the critical current density of these samples decreases with increasing concentrations of Sm. - Abstract: In this work, samples of a nominal composition $Y_{1}B{a}_{2-x}S{m}_{x}C{u}_3{O}_{7-\delta }$ With Sm substitution (X = 0.00, 0.01, 0.03, 0.05) were prepared by the solid state reaction method. And the effect of substituting Sm instead of Ba was investigated on the structural and superconducting properties of the samples. Measurement of electrical resistance and critical temperature was done using 4-Probe connection method. Results indicate that Sm substitution affects the YBSCO superconducting samples, decrease the transition temperature of the superconductor and increases the special electrical resistance and the transition width. Also, XRD studies show that in all samples of the Y–123 phase, the formation and structure is orthorhombic. SEM images showed that the porosity in the samples increased with increasing Sm due to disruption in grain growth and instead, increase Sm in the samples cause decreasing the size of the grain.