Reducing Toxic Thallium in Tl-2223 Cuprate

TL;DR

This study investigates how Li2O doping influences the synthesis, microstructure, and superconducting properties of Tl-2223 cuprate, revealing improved critical current density and synthesis conditions with optimal doping.

Contribution

It demonstrates that Li2O doping enhances critical current density and modifies synthesis and microstructure of Tl-2223, with optimal doping at 20%.

Findings

Li2O slightly decreases T_c but improves J_c.

Optimal 20% Li2O doping doubles J_c.

Short thermal annealing enhances superconducting volume and J_c.

Abstract

The present study gives an account of the effect of Li2O on the ease of phase formation and superconducting properties of Tl2Ba2Ca2Cu3O10+x (Tl-2223) material. Li substitution only slightly decreases the superconducting transition temperature, while the optimal concentration of 20% doping improves the critical current density (Jc) by ~ two fold. We found substantial effects on the synthesis temperature, microstructure and normal state transport properties of Tl-2223 with Li2O addition. Short-time thermal annealing under flowing Ar+4%H2 (1 hr.) further improves the superconducting volume fractions, as well as Jc.