The effect of Y substitution on Bi-2212 superconductor by sol-gel method

Superconductor material with the general formula of Bi2Sr2Ca1-xYxCu2O8 where "x" has values of 0.0, 0.05, 0.075, 0.1, 0.15 and 0.20 prepared with sol-gel technique by using oxide and hydrate elements is studied on its crystal, electronic and magnetic properties. Investigations on the crystal structure and morphological properties of the samples were carried by X-ray diffraction patterns and scanning electron microscopy images. To support the study, X ray absorption fine structure data were also collected at room temperatures. Influences of Y substitution on the properties of the material revealed that large Y atoms cause a disturbance in its environment and distort the crystal structure properties. Additionally, DC magnetization data were collected to study the effects of Y-substitution on the magnetic properties of the samples and gradual change in the physical and superconducting properties of samples were determined. Besides, temperature dependence of the magnetic behaviors of the samples were tested with the zero field cooled measurements and diamagnetic ordering below their onset temperatures were observed. From M-H loops, critical current density of the samples were evaluated by using Beans model and the best result collected from the sample with x = 0.05.