Electrochemical Detection of Ni ²⁺ Ions Using Synthesized (E)‐N’‐Chlorobenzylidene‐4‐methylbenzenesulfonohydrazide Derivatives Modified with a Nafion Matrix

Abstract ( E )‐ N ’‐Chlorobenzylidene‐4‐methylbenzenesulfonohydrazide (CBMBSH) compounds were synthesized using a simple condensation process from the derivatives of chlorobenzaldehyde and 4‐methylbenzenesulfonylhydrazine in a good yield which crystallized in ethanol. The CBMBSH molecules were totally characterized using conventional spectroscopic techniques such as 1 H‐NMR, 13 C‐NMR, FTIR, and UV‐Vis spectroscopy. The molecular structures of the CBMBSH molecules were confirmed using a single crystal X‐ray diffraction (SCXRD) method and used for the potential detection of heavy metal ion, nickel (Ni 2+ ) using a reliable I−V technique. A thin layer of CBMBSH was deposited onto a flat glassy carbon electrode (GCE) with 5 % nafion coating binder in order to modify a sensitive and selective Ni 2+ ionic sensor. Sensitivity, limit of detection (LOD), and limit of quantification (LOQ) of the modified electrode towards Ni 2+ were calculated from the slope of calibration curve as 949.0 pAμM −1 cm −2 , 98.0±2.0 pM, and 326.67 mM respectively. The approaching CBMBSH/GCE sensor was applied to the selective determination of Ni 2+ in spiked real samples, and found satisfactory and rational results.