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- Resumen es exacto "Chalcogenide glasses (base Te, Se or S) have been studied for years as sensitive membranes of ion selective electrodes (ISEs) for the detection of heavy metal ions in solutions. Their employ in ISE membranes presents several advantages over their crystalline counterparts and are easily deposited as thin films, which allows the miniaturization of the electrodes. The objective of this thesis was the study of the structural, electrical, optical and sensing properties of glasses of the AgGeSe and CuAgGeSe systems aiming to their application as sensitive membranes of chemical sensors, specifically ion selective electrodes and optochemical sensors. Bulk chalcogenide glasess and thin films were manufactured by melt quenching and PLD, respectively.
Structural properties of the glasses were studied through XRD, SEM-EDS and Raman spectroscopy, electrical properties were studied through impedance spectroscopy and optical properties were studied through spectrophotometry in the UV-Vis-IR range.
Ion selective electrodes were manufactured with bulk and thin films membranes and their sensing properties were studied: linear range, detection limit, stability, reproducibility, response time, selectivity and interfering ions effects. It was observed that both the ISEs with bulk and thin films membranes show a clear response to the presence of the ions Ag+, Cu2+ and Pd2+, a small response to the presence of the ions Cd2+ and Cr3+ and a total lack of response to the presence of the ions
Mg2+ and K+. It was concluded that, due to this mixed selectivity, the electrodes could be used in multisensor systems called electronic tongues. Finally, the high transmission in the near IR range, the high refractive index and the sensitivity to the presence of ions in solutions of all the films indicate that they are good candidates to be used in the manufacture. "
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