Preparation And Magnetic Properties Of BSCCO Superconducting Nanofiber

Since the discovery of superconducting materials,researchers worldwide have been closely examining the hot spot.Superconducting materials have vast potential in the fields of power transmission,transportation,electrical machinery,microelectronics,electronic computers,aerospace,communications,nuclear physics,new energy,biological engineering,medical treatment,and military equipment.Among these,1D nano-superconducting fibers,with their high specific surface area and excellent connectivity,exhibit distinct properties compared to conventional macroscopic bulk superconducting materials.Therefore,it is critical to improve the preparation method of nano-superconducting fiber materials and investigate their morphology and magnetic properties.This study focuses on the preparation of Bi₂Sr₂Ca Cu₂O_8+δ（Bi-2212）and Bi_2-xPb_xSr₂Ca₂Cu₃O_10+δ（Bi-2223）nano-superconducting fiber materials via electrospinning and solution blow spinning techniques,respectively.The microstructure and magnetic properties of these materials were analyzed.The main research content is as follow:1.Bi-2223 superconducting nanofibers were successfully synthesized by the electrospinning method,and the effect of Pb element substitution on the microstructure and magnetic properties of Bi_2-xPb_xSr₂Ca₂Cu₃O_10+δ（x=0,0.1,0.2,0.3,and 0.4）nanofiber networks was studied.The scanning electron microscopy images revealed that the superconducting grains grew continuously with increasing Pb content.Moreover,the relative volume fraction of the Bi-2223 phase increased from 53.50%to 93.98%with increasing Pb content,resulting in a gradual dominance of the Bi-2223 phase and the successful transition from Bi-2212 to Bi-2223 phase.Additionally,various magnetic properties were significantly improved.2.The superconducting transition temperature of Bi-2212 nanoscale superconducting fiber materials prepared by solution blow spinning is relatively low.However,by optimizing the preparation process and doping SiO₂nanoparticles,the size of the superconducting grains can be improved,and the connectivity between the superconducting grains can be enhanced.SiO₂ nanoparticles can also create pinning centers,which can directly and effectively achieve the most idealized superconducting pinning structure.Additionally,according to the Dew-Hughes model,both pure Bi-2212 and samples doped with SiO₂ nanoparticles exhibit activated point and surface pinning.3.Bi-2212 nanoscale superconducting fiber materials were prepared by both electrospinning and solution blow spinning,and a detailed comparative study of the microstructure and magnetic properties of Bi-2212 nanoscale superconducting fibers was conducted.The microstructure study shows that the fiber morphology prepared by different methods varies.The magnetic study shows that the Bi-2212 nanoscale superconducting fiber materials prepared by electrospinning have high superconducting transition temperature,magnetization intensity,critical current density,and pinning force density.