Transport properties of AgGeSe for Ion Selective Electrodes

CONDE GARRIDO JUAN MANUEL; SILVEYRA JOSEFINA M; UREÑA ANDREA M; ARCONDO BIBIANA

Congreso; Nanotechnoloy 2012; 2012

Materials Today

In the past three decades, solid-state Ion Selective Electrodes (ISEs) have incorporated advances in nanotechnology by using chalcogenide glasses as sensitive membranes. The chemical stability chalcogenide glasses guarantees high durability even in acid environments. These materials are easily synthetized and can therefore be used in the form of both bulk and thin films for developing sensitive membranes for low-dimensional sensors and multisensors arrangements. In this work, chalcogenide glasses of composition Agx(Ge0.25Se0.75)100-x (0 at. % ≤ x ≤ 25 at. %) were studied as a sensitive material for ISEs. For x ≥ 8 at. % the glasses are sensitive to Ag+ and Cu2+ ions in water-based solutions. For x < 8 at. % the electrodes response is poor. In order to understand the sensing properties of chalcogenide glasses, it is first necessary to know their electric properties. The goal of this work was to clarify if the sensing property of these materials in exclusively determined by the ionic conductivity or by the total resistance of the material. The materials were prepared in the form of bulk and thin films membranes. Thin films of some hundreds of nanometers thick were synthetized by Puled Laser Deposition (PLD). For x ≥ 8 at. %, the glasses system behaved as a ionic conductor (10-5 S/cm) For x < 8 at. % the system behaved as an insulator (