SYNTHESIS AND CHARACTERIZATION OF FESE SUPERCONDUCTORS BY THE ADDITION OF MG DOPING USING THE VACUUM METHOD

In this work, the powder preparation Fe0.99Se-Mg 1wt%. Iron, selenium powder, and magnesium powder are used as raw materials. The raw materials is milled using a mortar agate for 3 hours after weighed in the ratio of the atom Mg:Fe;Se = 0.01:0.99:1. To be characterized by the formation of Fe0.99Se-Mg 1wt%, the milled powder is then compressed into a pellet sample and sintered at 745˚C and 845˚C for 3 hours. All sample are sintered on furnance and cooled with room temperature. XRD are used to analyse forming phase. Based on the calculation of diffraction pattern, sample are sintered at 745˚C has a higher mass fraction of tetragonal phase than a sample that is sintered at 845˚C. the lattice parameter at 745˚C sample are a = 3.7790 Å and c = 5.5111 Å. According to the resistivity measurement results, it appears that the sample are sintered at 745˚C have a critical temperature ~ 13.4K.