Preparation of the Bi1.8Pb0.4Ca2Sr2Cu3Oy Superconductor with a Citrate Precursor Method

✍ Scribed by T.P. Wei; C.M. Wang; H.-C.I. Kao

• Publisher: Elsevier Science
• Year: 1994
• Tongue: English
• Weight: 191 KB
• Volume: 109
• Category: Article
• ISSN: 0022-4596
• DOI: 10.1006/jssc.1994.1097

✦ Synopsis

The (\mathrm{Bi}{1.8} \mathrm{~Pb}{0.4} \mathrm{Ca}{2} \mathrm{Sr}{2} \mathrm{Cu}{3} \mathrm{O}{y}) superconductor is prepared by a citrate precursor method. Nitrate salts of the constituent metals are dissolved in deionized water, and citric acid and ethylene glycol are added. The (\mathrm{pH}) of the solution is adjusted to 6.8. The solution is then dried at (80^{\circ} \mathrm{C}), pyrolyzed at (200^{\circ} \mathrm{C}), calcined at (810^{\circ} \mathrm{C}), pressed into pellets and sintered at (860^{\circ} \mathrm{C}) for (20 \mathrm{~min}), and lowered to (850^{\circ} \mathrm{C}) for different periods and cooling in the furnace or quenching in the air. The highest (T_{\mathrm{czeror})}) is (114 \mathrm{~K}), observed in a sample which is sintered for (24 \mathrm{hr}) and resintered for (96 \mathrm{hr}) with furnace cooling. The X-ray diffraction pattern shows that it contains (95 %) high (T_{c}) phase of (\mathrm{Bi}{2-x} \mathrm{~Pb}{x} \mathrm{Ca}{2} \mathrm{Sr}{2} \mathrm{Cu}{3} \mathrm{O}{y}) superconductor. (O) 1994 Academic Press, Inc.