Open AccessThe Role of Tl Substitution on Superconducting Properties for Hg-1223 System
Author(s) -
M. F. A. Alias,
Bushra A. Aljurani,
Ghazala Y. Hermiz
Publication year - 2020
Publication title -
iop conference series. materials science and engineering
Language(s) - English
Resource type - Journals
eISSN - 1757-899X
pISSN - 1757-8981
DOI - 10.1088/1757-899x/757/1/012057
Subject(s) - tetragonal crystal system , analytical chemistry (journal) , sintering , impurity , lattice constant , superconductivity , materials science , oxygen , solid solution , transition temperature , diffraction , crystal structure , nuclear chemistry , crystallography , chemistry , metallurgy , physics , organic chemistry , chromatography , quantum mechanics , optics
High temperature superconductors with a nominal composition Hg 1-x Tl x Ba 2 Ca 2 Cu 3 O 8+δ for (0<x<0.4) were prepared by two-step solid state reaction in air. The effect of the substitution of Tl for Hg, oxygen content (δ) and sintering time (20-200h) on the Hg-12223 superconductivity system has been investigated to obtain the optimum conditions for the formation and stabilization of the high critical temperature (T c ).The results showed that the optimum sintering temperature for the prepared samples was equal to 880 °C, whereas the sintering time is equal to 100 h.The quantity of the element content for Hg 1-x Tl x Ba 2 Ca 2 Cu 3 O 8+δ system were carried out using x-ray fluorescence (XRF). X-ray diffraction (XRD) analysis showed a tetragonal structure with a high T c phases (1223) as a dominant phase and low T c phase (1212) addition to exist of some impurity phases for all samples. It was found that the change of the Tl concentrations of prepared samples produced a change in the lattice parameters, density ρ m and c/a ratio. The highest T c for HgBa 2 Ca 2 Cu 3 O 8+δ composition was 118 K. The results for the doped samples, represented highest Tc equal to 124 K for Hg 1-x Tl x Ba 2 Ca 2 Cu 3 O 8+δ sample with x=0.4.The oxygen content was not systematic changed but it played a great role in the evaluation of T c .