PURPOSE: To obtain mixed metal oxides which are adequate for a laser cathode, etc., and is homogeneous and do not contain foreign materials, by bringing the soluble salts of plural metals and quaternary ammonium carbonate into reaction and drying and calcining the mixed carbonates of the settled metals.
CONSTITUTION: CO2 is blown into an aq. soln. of quaternary ammonium hydroxide (e.g.; tetramethylammonium hydroxide) to form the soln. of the quaternary ammonium carbonate (e.g.; tetramethylammonium carbonate). The soln. of the soluble salts of the plural metals (e.g.: lanthanum nitrate, strontium nitrate, cobalt nitrate) is added to the soln. of pH about 7.7 to 10 to effect reaction and to allow the mixed carbonate of the metals to settle. The precipitate is then recovered and dried and is then calcined. The mixed metal oxides (e.g.; La0.7Sr0.3CoO3), which are homogenous at an atom level, do not contain foreign contaminating materials and are useful as ceramics, are obtd.
UI HIN PAN
JIYON AREN RUDESHIRU
Next Patent: SUPERCONDUCTING THIN FILM AND ITS FORMATION