Synthesis And Properties Of Ba_1-xA_xBi_1-yM_yO₃Superconductors

Along with the discovery of high-Tc copper-oxide superconductors,BKBO was found to be the first copper-free oxide superconductor withTc>30K. BKBO has a simple cubic perovskite structure with isotropicsuperconductivity. In this dissertation, we have adopted the topologicreaction to prepare superconducting bismuthate. We succeed insynthesizing single Phase BKBO samples by accommodating the wightratio of precursor and molten salt, sintering temperature and reaction time.The bismuthate superconductors were characterized by means of X-raypowder diffraction, Superconducting quantum interferometer,Transmission Electron Microscope, Scanning electron microscope andInductively coupled plasma-atomic emission spectrometer et al. At thesame time, we discuss the preparation conditions of BKBOsuperconductors. It was found that a series of single-phase BKBOsuperconductors was synthesized at450°C for4hours when the wightratio of precursor and molten salt was1:5:2.5.Through the topology reaction we synthesized new bismuthatesuperconductor Ba1-xKxBi1-yTayO3, Ba1-xKxBi1-ySbyO3, Ba1-xKxBi1-yLayO3. In this dissertation, the research will provide a new thought forexplore the new bismuthate superconducting materials.