CHARACTERIZATION OF X)AGI-CENTER-DOT-YCU(2)MOO(4)CENTER-DOT(50-Y)CUPO3 GLASSES

The xCuI . (50 - x)AgI . yCu(2)MoO(4) . (50 - y)CuPO3 glasses with var ious compositions corresponding to 20 < x < 50 and 15 <y < 37.5 mol % have been prepared by melting the required constituents in an inert at mosphere and quenching in ice cold water. The glass samples are charac terized by DSC, AFM, FTIR, XPS, and conductivity techniques. The IR st udy shows that the main IR bands nu(s) PO3-, nu(1)PO(4)(3-), nu(4)PO(4 )(3-) and nu(1)MoO(4)(2-) at 1030, 990, 590 and 940 cm(-1) change thei r wave number systematically when CuI is replaced by AgI. XPS results indicate the presence of both Cu+ and Cu2+ and the lowest percentage o f Cu+ is 69.7%. XPS results show that the condensed group units like P O3- and P2O74- change in binding energy when doping salt is introduced . It is believed that it is caused by doping salt distributed in the i nterstitial positions resulting in phase separation when dopant conten t is particularly high. A phase separation model has been proposed to illustrate the behaviour of these materials. The source of electronic conductivity in this system is principally from Cu2+ ions existing in host network.