The preparation of high T sub c superconductors from nitrates.

The preparation of high T sub c superconductors, in most cases, proceeds by ceramic methodology from the metal oxides and carbonates. In this paper we show that the same materials can easily be derived from nitrates. When the appropriate mixture of nitrate salts is prepared and ground together, then fired, in air, and in pure oxygen, the superconducting material results. Both the La sub (1.85) Sr sub (0.15) CuO sub 4 and Ba sub 2 YCu sub 3 O sub 7 materials have been prepared in this way. Their authenticities have been confirmed by comparison of their x-ray powder patterns and resistivity properties with those published for known materials. In addition we have demonstrated that solutions of nitrate salts can be analyzed for purity by a simple spectroscopic method.