Electrochemical oxygen intercalation in La2CuO4 prepared by nitrates method: Microstructural effects

In order to determine microstructural effects in the electrochemical oxygen intercalation for La2CuO4, and the relative abundance of the two supercond ucting phases (T-c=33 and 44K), this oxide was prepared using the nitrates method, which involves the dissolution of La and Cu oxides in nitric acid. The product was pressed as pellets. A narrow grain size distribution and a density higher than 95% rho (T) was obtained. After electrochemical oxygen intercalation, at room temperature, this material gave a main superconducti ng phase with T-c=33K, whereas porous pellets obtained from the same oxide, with intermediate grinding, gave a T-c=44K.