抄録
Two kinds of methods were carried out in order to dope the oxygen in La2CuO4 crystals; the annealing under high oxygen pressure at high temperature and the electrochemical oxidation in an aqueous alkaline solution at ambient temperature. The difference in the orthorhombicity was seen in La2CuO4+z with the same z value, prepared by different routs, which indicates the different excess oxygen distribution. The electrochemical oxidation is also effective to bring the superconductivity in La2-xBixCuO4+z and La2-xPbxCuO4+z. Some samples show the Tc on set of 30K for Bi doped system and 15-20K for Pb doped one.
