Investigation of Influence of Various Nanoparticle Materials on the Response Performance of an Iodide Selective Carbon Paste Electrode

In this research the influence of various nanoparticles such as, oxidized multiwall carbon nanotubes (MWCNTs), nanoparticles of palladium, gold, platinum, silver, zinc sulfide and zinc oxide loaded on activecarbon on the response properties of an iodide carbon paste electrode based on Iron(II)phthalocyanine as suitable carrier are investigated. It was seenamong different nanoparticles, the best electrode response (wide linear range, low detection limit, best selectivity and fast response time) wasobserved in presence of nanoparticles of palladium. To achieve nernstian response over a wide linear range, the effects of various parameters such as amount of ionophores, amount of additive and amount of nanoparticles on the response properties of proposed electrode were investigated and their values was set as Carbon powder, Pd-NP-AC: Nujol, Carrier, MTOACl,(0.15 g, 20 mg, 25 mg, 4.0 mg, 2.4 mg) respectively.. The electrode exhibits a Nernstian slope of 59.3 ± 0.7 mV decade-1 over a wide concentration rangefrom 5.0×10-8 to 1.0×10-1 M with detection limit of 3.0×10-8 M in presence of nanoparticle of palladium. It has relatively fast response time (10 s) andrelatively long life times (2 months). The electrode response is independent of the solution pH in range of 3.0–11.5. This electrode has been applied forpotentiometric determination of iodide ion in real samples and as indicator electrode for potentiometric titration of iodide solution with AgNO3.

Keywords:

Nanoparticles , Electrochemical sensor , Iodide ion , Carbon paste electrode