Platinum nanoparticles intermediate layer in solid-state selective electrodes

Abstract

A platinum nanoparticles (PtNPs) layer is used for the first time as an ion-to-electron transducer in a solid-state ion-selective electrode (SC-ISE). The electrode was prepared by adding the PtNPs as an intermediate layer between the ionophore-doped solvent polymeric membrane and the electrical conductor. The PtNPs layer was characterized by high resolution transmission electron microscopy, selected area electron diffraction and X-ray photoelectron spectroscopy. The stability of the electrical potential of the new solid-contact electrode was examined by performing current-reversal chronopotentiometry while the influence of the interfacial water film was assessed by the potentiometric aqueous-layer test. The performance of the new electrode was evaluated by determining K⁺. The new electrode presented a Nernstian slope, a very good reproducibility of the standard potential values and a small potential drift.