Potentiometric Sensors Based on Cobalt–Polymer Composites for Cobalt (II) Ions

The development of novel potentiometric sensors for cobalt (II) ions in aqueous solutions is reported here. Cobalt-polymer composites have been used to produce cobalt-selective membranes. Analytical characteristics of the proposal sensors have been determined. Morphological investigation allows revealing the formation of the endless conductive cluster in the threshold area of cobalt metal concentrations. The existence of such a structural unit makes possible the usage of the elaborated composites as a sensitive membrane for ion-selective electrodes. Results obtained from X-ray photoelectron spectroscopy prove the formation of cobalt-polymer complexes in these composites. Strong cobalt-polymer interaction is detected by the X-ray diffraction method. Metal-polymer complexes determine the electrochemical properties of the composite ion-selective membranes. Composite cobalt-selective electrodes can find application in a chemical or ecological monitoring for the presence of Co (II) ions.