Method of preparing Pb-Sr-Ca-Ln-Ca-O metal oxide superconductor

摘要

An oxide superconductor having the following formula: Pb2Sr2Ca1-pLnpCu3Oq or Pb1-xCuxSr2Ca1-yLnyCu2Oz wherein Ln represents a rare earth element, p is 0.3-0.7, q is 7.8-8.2, x is 0.2-0.5, y is 0.3-0.7 and z is 6.8-7.2 is prepared using a coprecipitation method. An acetic acid solution of carbonates, acetates or nitrates of Pb, Sr, Ca, Cu and Ln is mixed with an aqueous solution of oxalic or tartaric acid, or a lower alkyl ester thereof. The mixture is reacted to precipitate the Pb, Sr, Ca, Cu and Ln as oxalates or tartarates and the precipitates are dried and sintered to obtain the oxide superconductor.