Pb(II)-ion-selective electrodes based on chalcogenide glasses

Novel chalcogenide glasses (ChG) from the GeSe ₂ –PbSe–PbTe system were investigated as membrane materials in ion-selective electrodes reversible to Pb(II)-ions. Pb(II)-ion-selective electrodes (Pb(II)-ISE) of ‘coated wire’ type were constructed, which consist of standard Ag/AgCl electrodes uniformly coated with a composite mixture of polymer filled with GeSe ₂–PbSe–PbTe glassy powder. The basic analytical characteristics of Pb(II)-ISE, such as reproducibility, linear range ( L), slope of the electrode function ( S ), limits of detection (LD), working pH-range and response time ( τ ₉₅), were studied with respect to the ChG composition. The cross-selectivity in the presence of some interfering ions, which commonly attendant Pb ²⁺-ions in analytical media, was investigated. Potential-generating mechanism was suggested explaining sufficiently the observed dependencies.