Development of 5,5′-Bi(1,10 Pvc Membrane Potentiometric Sensor for Silver Determination

Abstract

In this study, the selectivity of the 5.5 '-bi(1,10-phenanthroline) Compound (1) against Ag+ ions as a chemical sensor was investigated by both absorption and potentiometric methods. First, a 1 x 10(-5) M solution of Compound (1) in acetonitrile was prepared. For the selectivity test, 1 x 10(-2) M solutions of metal ions in acetonitrile were prepared. UV-visible absorption measurements were performed by adding metal ions to a 5.5 '-bi(1,10-phenanthroline) compound at certain concentrations. Among the studied metal ions, it was found to be selective only against silver ions. In addition, solid-state contact polyvinylchloride (PVC) membrane electrodes prepared using 5.5 '-bi(1,10-phenanthroline) as an ionophore were found to be selective against Ag+ ions among other ions. The optimum membrane composition of the measurement was determined as 3% 5.5 '-bi(1,10-phenanthroline) + 32% PVC + 64% o-nitrophenyl octyl ether (o-NPOE) + 1% potassium tetrakis(4-chlorophenyl) borate (KTpClPB). The potentiometric properties of the silver selective electrode were determined as linear working range 1.0 x 10(-7)-1.0 x 10(-3) M, detection limit 1.0 x 10(-7) M, pH working range 3.23-9.08, and response time 3 s. Absorption and potentiometric methods confirm the selectivity towards silver ions. The IRC analysis of the silver-containing complex, performed using the DFT/B3LYP method with the LanL2DZ basis set, reveals an activation energy of approximately 0.002 Eh, with the transition state energy at -1.433173 Eh.