Single phase materials of La1 + xBa2 - xCu3Oz with x = 0.0, . . . ,0.98, were synthesized from highly homogeneous precursors, prepared by spray-drying or the polymerized complex method. These samples were characterized using X-ray diffraction (XRD), Raman spectroscopy and AC susceptibility measurements. The effects of composition, processing time, temperature and oxygen partial pressure, on the formation and decomposition of La1 + xBa2 - xCu3Oz prepared by different methods, were investigated. We found that: Tc gradually decreased with the increase of La content; orthorhombic distortions appear at x < 0.25 and x > 0.7; and single phase stoichiometric La-123 ceramic samples, obtained at low oxygen partial pressure and quenched, decomposed into La-123ss (x = 0.2) and BaCuO2 after annealing at a rather low temperature, below 500°C.
ASJC Scopus subject areas
- Physics and Astronomy(all)