The sensing properties of two chalcogenide materials were investigated. It is shown that membranes based on the PbI2-Ag2S-As2S3 and PbS-Ag2S-As2S3 materials show sensitivity to the presence of Pb2+ species in solution. In both cases they exhibit near-Nernstian response. We mainly focused on the best matrix. The basic physicochemical parameters were then measured. The developed ISE exhibits a near-Nernstian slope of 27 mV/decade versus Pb2+ in the range of 10−5,5 - 10−3 M. Moreover the proposed Pb-SE shows excellent out-put signal in the presence of foreign ions. The analytical properties such as reproducibility, response time, and stability were studied. We report a multi-sensor process that we developed for in-situ real-time monitoring of waste water. The very first results of prototype measurements are presented.

Cadmium chalcogenide thin films were deposited by different processes. Pulsed laser deposition, thermal evaporation, and sputtering were used to elaborate micro devices on glass substrate from CdS-AgI-Ag2S-As2S3, CdS-Ag2S-Sb2S3 and Cd-Ag-As2S3 starting materials respectively. The micro films were characterised using scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), X-ray diffraction (XRD) and electrochemistry. Comparative structural characterisation leads us to understand sensors out-put signal. The best miniaturised sensor was selected. The very first electrochemical results are presented. The potentiometric response of Cd-Ag-As2S3 sensing matrix showed a quasi-Nernstian behaviour with a great detection limit. Moreover Cd-ISE is sensitive to silver (+I) in solution.