Türk Doğa ve Fen Dergisi, vol.12, no.1, pp.44-52, 2023 (Peer-Reviewed Journal)
This study concerns the remarkable variations in the crystalline quality, phase compositions, superconducting properties, and pinning force in the Bi-2212 ceramics through the addition of Co3O4 nano-particles with the x % weight for x = 0, 0.5, 1, and 2, respectively. From XRD analysis, it is deduced that Co3O4-inclusions give rise to the XRD peaks to expand, degrade the crystal quality together with a decrement in the Bi-2212 amount. From SEM images, it is seen that there is an evolution from rod-like structure to plate-like structure with Co3O4 addition. The critical transition temperature (Tc) value which is determined from M-T measurement is 82 K in the pure sample, it drops gradually and takes the value 65 K and 42 K for the 0.5% Co sample and 1% Co sample respectively, and eventually, the superconductivity is lost in the 2% Co sample. From M-H measurements, it is clear that the hysteresis loop gets narrower with Co3O4 addition and temperature. Accordingly, critical current densities (Jc) and pinning forces (Fp) reduce due to deteriorations in the connectivity between superconducting grains induced by the augmentation in Co3O4 content.