A new kind of nanocomposite with highly ordered AgI nanowires embedded in an anodic aluminium oxide membrane was fabricated by low-temperature step-electrochemical growth. Structural evolution, phase transition, and ionic conductivity were investigated by X-ray diffraction, differential scanning calorimetry, and impedance measurements. The phase transition from β/γ-AgI phase to α-AgI phase occurred at temperature of 168C, that is, higher than that of reported bulk AgI (147C); abnormally, the α to β/γ phase-transition temperature on cooling was also depressed as large hysteresis formed. The high-temperature phase, namely, α-AgI, remained at temperatures as low as 80C. The initial highly oriented-growth AgI nanowire disappeared after undergoing heating and cooling processes and a mixture of polycrystalline β/γ-AgI and amorphous-like interface phases formed. The cooled AgI plus anodic aluminium oxide composite displayed ionic conductivity in the order of 10−2S/cm at room temperature. This array-structured nanocomposite of AgI plus anodic aluminium oxide may be further developed for usage as a new type of battery, i.e., “nanobatteries” and “nanosensors” with individual AgI nanowires as basic elements.

Anomalous Phase Transition and Ionic Conductivity of AgI Nanowire Grown Using Porous Alumina Template. C.Liang, K.Terabe, T.Hasegawa, M.Aono, N.Iyi: Journal of Applied Physics, 2007, 102[12], 124308