Preparation of Bi-system superconductor using sol-gel method

Abstract

The citrate gel of (Bi, Pb), Sr, Ca and Cu and the (Bi, Pb)-Sr-Ca-Cu-(O, F) superconductor were prepared using citrate as the organic complex agent and 2-ethyl hexanol as the dehydrating agent. The starting material was a high-purity nitrate solution containing the desired ions in the appropriate atomic ratio. The optimum temperature and pH to obtain the homogeneous gel precursor were estimated. IR and DSC were employed to study the thermal decomposition and the calcination of the precursor material. After the calcined powder was sintered, a nearly single-phase (Bi, Pb)₂Sr₂Ca₂Cu₃O_x superconductor with the transition temperature 105 K was synthesized. The effect of the doping of Pb and F was also studied in the paper.

Keywords

sol-gel method / Bi-system superconductor / citrate-2-ethyl hexanol-nitrate system