| Summary: | High-temperature superconductor ceramic of low-density Bi1.6Pb0.4Sr2 (Ca2-xEux) Cu3Oy both doped and non-doped, have been produced by the method of conventional solid state reaction synthesis. The effects of rare earth doping on low-density superconductor compound have been studied by considering the Eu substitution at Ca site to stoichiometric of Bi (Pb)-2223 with x ranging from 0.000 to 0.2000. The experimental works in this study consists of direct-current (DC) electrical resistance-temperature and critical current density measurements for both electrical and superconducting properties, powder X-ray diffraction (XRD) for phase analyses and lattice parameters, and field emission scanning electron microscopy (FESEM) for surface morphology. All the Eu-doped samples comprised of both low-Tc Bi (Pb)-2212 and High-Tc Bi (Pb)-2223 phases. The substitution of Eu at the Ca site induced the reduction of volume fraction for the Bi (Pb)-2223 phase and the increment of the volume fraction for Bi (Pb)-2212 phase. Eu doping did not enhance the Tc zero but gradually reduced its value and become semiconducting at a high dopant concentration with x=0.200. From FESEM investigation, the grain size started to degrade from x=0.000 to x=0.0100 and form smaller plate-like grain which belong to Bi(Pb)-2212 phase and the grain particles seem to be coagulated to form clusters for x=0.200. © 2016 Trans Tech Publications, Switzerland.
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