Polyaniline/Al Bismuthate Composite Nanorods Modified Glassy Carbon Electrode for the Detection of Benzoic Acid

Abstract

Context: Benzoic acid is a kind of extensively used preservative. It is of great significance to detect benzoic acid by a rapid method for quality assurance and protection in the fields of pharmaceutical, food and chemistry industry. Objective: The present research is aimed to prepare polyaniline/Al bismuthate composite nanorods by an in-situ polymerizing process for effective detection of benzoic acid. Methods: The polyaniline/Al bismuthate composite nanorods are prepared by an in-situ polymerizing process. The structure, morphology and electrochemical performance of the obtained polyaniline/Al bismuthate composite nanorods are analyzed by X-ray diffraction (XRD), transmission electron microscopy and electrochemical measurement. Results: XRD and transmission electron microscopy observations show that the amorphous nanoscale polyaniline particles attach to the surface of the crystalline nanorods. The electrochemical measurement of 2 mM benzoic acid using the composite nanorods modified glassy carbon electrode (GCE) shows that a pair of semi-reversible CV peaks is located at -0.11 V (cvp1) and -0.48 V (cvp1′), respectively. The electrochemical responses of 2 mM benzoic acid at the composite nanorods modified GCE are enhanced with increasing the scan rate and benzoic acid concentration. The polyaniline/Al bismuthate composite nanorods modified GCE shows a linear range of 0.001-2 mM with the limit of detection (LOD) of 0.18 µM. Conclusion: The composite nanorods may be used as the electrode materials with good reproducibility and stability for the detection of benzoic acid.