SYNTHESIS AND CHARACTERIZATION OF NANOSTRUCTURED POLYANILINE SUPPORTED g‒C3N4/ZnO/CeO2 SENSOR FOR MALATHION DETECTION

Abstract

In this study, PANI/g‒C3N4/ZnO/CeO2 modified glassy carbon electrode (GCE) electrochemical sensor was developed for the detection of malathion. The structure, optoelectronic properties, surface functional groups, morphology, thermal stability and surface area of the nanocomposites were characterized by X-ray diffraction (XRD), UV-Vis spectroscopy, Fourier transform infrared (FTIR), Scanning electron microscopy (SEM), Thermogravimetric Analysis (TGA) and BET analysis. Cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS)) were used to investigate the electrochemical behavior GC modified electrode by the various as produced nanocomposite in the presence of 2 mM K3Fe(CN)6/0.1 M KCl and 0.1 M phosphate buffer(PBS). The recorded voltammogram indicated that enhanced electrochemical signal was observed in the case of PANI/g‒C3N4/ZnO/CeO2/GC electrode. Besides, the same electrode showed smaller charge transfer resistance as noticed from EIS spectra. These could be most probably due to contributions coming from the high conductivity of g‒C3N4 and catalytic effect of both ZnO and CeO2. To improve the performance of PANI/g‒C3N4/ZnO/CeO2/GCE sensor for the detection of malathion, pH of PBS solution and scan rate were optimized. Under optimized experimental conditions (pH = 7.0 and = 50 mVs-1 ) the concentration of malathion in standard solutions from 2.0 × 10−8 to 14.0 × 10−8 M was determined using differential pulse voltammetry. The sensor exhibited a linear range 2.0 × 10−8 to 14.0 × 10−8 M, sensitivityPANI/g‒C3N4/ZnO/CeO2/GCE sensor was applied to determine the level of malathion in khat. The findings demonstrated that the sensor developed from these nanomaterials can be a good candidate for the non-enzymatic determination of malathion in various samples.

11.85 µA/µM and low detection limit of 10.94 × 10-9 M. In addition to this,