Abstract:

In this study, a 44-DABP/PGE modified electrode was prepared by coating graphite pencil electrode (PGE) surface with 4,4'-diaminobenzophenone (44-DABP) molecule. The coating process was carried out using the cyclic voltammetry (CV) method, in 1×10-4 mol L-1 44-DABP solution, with the number of 10 cycles between -1.5 V and +1.5 V with 0.1 Vs-1 scan rate. The prepared 44-DABP/PGE electrode was characterized by electrochemical methods using CV and electrochemical impedance spectroscopy (EIS) techniques. In addition, the electrochemical behavior of 2-nitrophenol (2-NP) on the 44-DABP/PGE surface was investigated using CV and differential pulse voltammetry (DPV) techniques, and then the voltammetric determination was performed with the DPV technique. With the 44-DABP/PGE electrode, optimum conditions such as supporting electrolyte and pH suitable for 2-NP determination were determined. Under optimum conditions, it was determined that the current value of the reduction peak of 2-NP increased approximately 20 times by modifying the PGE electrode surface with 44-DABP. The working range for 2-NP with 44-DABP/PGE modified electrode was found as 0.75–15 µM and the detection limit (LOD) was 0.51 µM. It has been found that the 44-DABP/PGE electrode has good repeatability for the 2-NP determination. The determination of 2-NP in tap water by using the modified electrode has been successfully performed using the standard addition method with a good recovery and low relative standard deviation.

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