Ion conduction in one-dimensional ionic conductor AxGa8Ga8+xTi16−xO56 (A=K, Rb, Cs)
Abstract Conduction of ions blocking the motion of mobile alkali ions in single crystal of one-dimensional (1D) superionic conductor alkali gallotitano-gallate AxGa8Ga8+xTi16−xO56 (A=K, Rb, Cs) was studied by an AC complex electrical conductivity measurement from 20 Hz to 98 GHz. Data were analyzed by the moving box model. The complex conductivity of blocks showed the power law for frequency. The conduction process was thermally activated and values of the activation energies were large, 1.22, 1.20, and 1.05 eV for KGGTO, RGGTO, and CGGTO, respectively. The conduction mechanism was discussed by the motion of the extra oxygen ions in the conduction path (1-D tunnel) and the push-pull motion of the Ga3+ ions between the tetrahedral site in the tunnel framework and interstitial sites in the conduction path.