Optical, electrochemical, and sensing properties of (E)‐2‐[[(4-hydroxyphenyl)imino]methyl]phenol for the detection of iodide ions

An electrochemical sensor based on ( E )-2-[[(4-hydroxyphenyl)imino]methyl]phenol (anil) was developed for the detection of iodide anions. The complexation ability of the anil with I − , Br − , Cl − , CN − , SCN − , NO 3 - , CH 3 COO − , SO 4 2 - , F − , and S 2− was explored by UV–Vis spectroscopy. The results showed that the proposed probe has high sensibility for the detection of I − , with the absorption intensity changing due to the formation of anil–I − complex. The anil and iodide anion bind by a 1:1 complex stoichiometry and the association constant is determined to be 8.5 × 10 3 M −1 . In addition, the sensing film was elaborated by drop coating on a platinum electrode. The electrochemical sensors for the detection of I − were analyzed by DPV. It showed a linear response in the range of 1 × 10 –7 to 1 × 10 –4 M, with a low detection limit of 4 × 10 –8 M. The sensor shows good analytical performance. The developed sensor is suitable for application in water quality monitoring. Graphical abstract