Electrochemical preparation of YBaCu oxide layer on copper

Abstract

A new electrochemical method to prepare an oxide layer of yttrium, barium and copper on a copper substrate has been developed. A nitrate solution of yttrium, barium and copper in the molar proportion 1:2:3 with citric acid and ethylene glycol is stirred and heated to form a gel. The gel is decomposed by heat and ground into fine powders. The copper substrate is anodized in 4 M sodium hydroxide solution at 80–85 °C to form a flexible copper oxide layer. The powders are coated or pressed on the substrate and then heat treated. The electrochemically formed oxide layer is well sintered to the coated powders. The resulting oxide layer was observed by scanning electron microscopy, analysed by X-ray diffractometry and characterized in terms of its resistance change as the temperature falls. The presence of copper oxide shifts the superconductivity to semiconductivity.