Abstract
Much attention has been given to detection and monitoring of hydrazine-based compounds in recent time because of its significant negative impacts on human health and ecosystem (aquatic lives). This prompted the current study focusing on detection of 2, 4-dinitrophenylhydrazine (2, 4-dnphz) using electrochemically synthesized poly-para amino benzoic acid-manganese oxide (P-pABA-MnO2) composite film. The synthesized P-pABA-MnO2 composite film was characterized in terms of its structural and morphological properties by X-ray diffraction spectroscopy and field emission scanning electron microscopy respectively. In addition, functionalities and binding energy of p-PABA-MnO2 were confirmed using Fourier transform infrared spectroscopy and X-ray photoelectron spectroscopy respectively. Finally, electrochemical properties were investigated using electrochemical impedance spectroscopy and cyclic voltammetry. The synthesized P-pABA-MnO2 displayed good electrocatalytic reduction property towards 2, 4-dnphz with ultra-low limit of detection (0.08 mu M; S/N = 3) and very high sensitivity (52 mu A mu D-1 McmD(-2)). The proposed sensor based on P-pABA-MnO2 also demonstrated good stability in terms of repeatability, reproducibility and interferents effects. Lastly, the proposed sensor was satisfactorily used in detection of 2, 4-dnphz in environmental real samples.