Cd-ISe and membrane technique device for in situ monitoring

The response of cadmium (II) ion-selective electrodes based on chalcogenide glassy matrix CdS-AgI-Ag2S-As2S3 is described. The electrode exhibits a Nernstian slope of 29 mV per decade in a large range of Cd2+ ion and a detection limit of 10(-7) M. Physical and electrochemical characteristics of ion-selective electrode are presented. The chalcogenide membrane/solution interface has been investigated using X-ray photoelectron spectroscopy (XPS) in order to understand the sensing properties. The second part is devoted to a system allowing detection of toxic species at low concentration. The preconditioning module is based upon electro-dialysis and the first tests conducted on model solution are presented.