Thin cathodically electroplated chalcogenide-based ion-selective membranes for flow-injection application

An overview is made of the research work carried out in the author's laboratory, which is aimed at developing thin ion-selective chalcogenide membrane by induced cathodic electrodeposition onto inert conducting substrate at controlled potential of the membrane's components. The most important analytical results from implementing them in flow-injection analysis are presented. The basic principle and the major advantages of the electrochemical approach are outlined, with an emphasis on its contribution to obtaining new optimized membrane formulations such as Cu2-xSe, CuAgSe, and Ag2+ō Se1−xTex with improved dynamic and surface properties. Selected examples of the performance of the newly developed ion-selective flow-injection potentiometric (ISFIP) detectors for Cu(II), Hg(II), Ag(I), and CN− ions are considered with regard to lower linearity limit, selectivity, long-term stability as well as unique FIP applications. A comparison with the dynamic behavior of the commercially available ion-selective electrodes or their second-kind electrode counterparts prepared by anodic dissolution helps to reveal the aspects of the competitiveness of the proposed ISFIP detectors.