Elemental Substitution at Tl Site of Tl 1- x X x (Ba, Sr)CaCu 2 O 7 Superconductor with X = Cr, Bi, Pb, Se, and Te

• Published in: Materials 2023-05, Vol.16 (11)
• Main Authors: Nur-Akasyah, Jaafar, Abd-Shukor, Roslan, Chong, Tet Vui
• Format: Article
• Language: English
• ISSN: 1996-1944; 1996-1944

The effects of elemental substitutions at the Tl site of a Tl X (Ba, Sr)CaCu O superconductor with X = Cr, Bi, Pb, Se, and Te were investigated. This study aimed to determine the elements that enhance and suppress the superconducting transition temperature of the Tl X (Ba, Sr)CaCu O (Tl-1212) phase. The selected elements belong to the groups of transition metal, post-transition metal, non-metal, and metalloid. The relationship between the transition temperature and ionic radius of the elements was also discussed. The samples were prepared by the solid-state reaction method. The XRD patterns showed a single Tl-1212 phase was formed in the non- and Cr-substituted ( = 0.15) samples. The Cr-substituted samples ( = 0.4) showed a plate-like structure with smaller voids. The highest superconducting transition temperatures ( , , and ) were also achieved by the Cr-substituted samples for = 0.4 compositions. However, the substitution of Te suppressed the superconductivity of the Tl-1212 phase. ( ) for all samples was calculated to be in the range of 12-17 A/cm . This work shows that substitution elements with a smaller ionic radius tend to be more favorable in improving the superconducting properties of the Tl-1212 phase.