New modified selective platinum electrode based on poly (ethylene glycol) for Iron (III) detection in real water

Abstract

Purpose This work aims to determine iron (III) in real water by using a new amperometric sensor on the basis of polyethylene glycol (PEG) to test and characterize a new modified selective platinum electrode. Design/methodology/approach In this review, the authors focus on testing and characterizing several polymeric membranes by using cyclic voltammetry and square-wave voltammetry (SWV) methods to differentiate the nature of plasticizers (2-Nitrophenyl octyl ether [NPOE], Di-n-octyl phthalate, Bis (2-ethylhexyl) sebacate, PEG. The authors have evaluated the possibility of using crown ether and three zeolite ionophore (faujasite [FAU], Chabazite and ZSM-5) matrixes as novel materials for the selective determination of iron (III) using SWV for the best membranes. Findings The results demonstrated that the modified platinum electrode presents linear dependence of amperometric signal with a wide linear range of 10−9 to 10−4 mol.L−1 for iron determination, revealing a detection limit of 10−10 mol.L−1 and amperometric sensibility of 58.58 µA/mol.L−1. The slope of the membrane plasticized with PEG calibration curve is six times higher than that of the other membranes. It was noticed that when the crown ether and the three zeolite ionophores were used, as a new detective material for iron with the membrane plasticized with PEG, the expected results were highly proven. The modified platinum electrode showed high selectivity to iron (III) when the heavy metal ions such as Ni (II), Al (III), Zn (III), Cd (II), Gd (II) and Cu (II) were present. Originality/value The utility of the method and the efficiency of the best membrane sensor have been accurately tested by the determination of iron in real water samples of Hassi Messaoud, south of Algeria.