Application of Nanostructured TCNQ to Potentiometric Ion-Selective K+ and Na+ Electrodes

作者：Paczosa Bator Beata^*; Piek Magdalena; Piech Robert

来源：Analytical Chemistry, 2015, 87(3): 1718-1725.

DOI：10.1021/ac503521t

A new type of potentiometric solid-state ion-selective electrode (SS-ISE) has been fabricated with an intermediate layer made of 7,7,8,8-tetracyanoquinodimethane (TCNQ) or its ion-radical salts and an ionophore-based ion-selective membrane. To show the influence of the TCNQ layer on electrode selectivity, sodium- and potassium-sensitive membranes were applied. A good Nernstian response with a slope of 59.24 mV/dec in the range from 10(-6.5) to 10(-1) M KCl and 58.68 mV/dec (10(-6) to 10(-1) M NaCl) was observed. The influence of an interfacial water film was assessed by an aqueous-layer test performed during potentiometric measurements. The stability of the electrical potential of the new solid-contact electrodes was tested by performing current-reversal chronopotentiometry, and the capacitance of the electrodes is 132 mu F or 154 mu F for K+ and Na+ solid-contact electrodes. These properties confirmed the analytical applicability of TCNQ-based SC-ISEs and should allow the development of a new solid-state ion sensor group.

• 出版日期2015-2-3