Highly sensitive voltammetric detection of 4-nitrobenzoic acid using Zn2SnO4/porous graphene oxide nanosheets composite electrode

초록

Detecting 4-nitrobenzoic acid (4-NBA) is crucial due to its prevalence as an industrial pollutant and associated health hazards. In this study, we synthesized a novel stannate-based nanocomposite, Zn2SnO4/porous graphene oxide nanosheets (Zn2SnO4/PGO), through a facile hydrothermal method followed by ultrasonication-assisted dispersion. For the first time, this Zn2SnO4/PGO nanocomposite was employed as an electrode modifier for 4NBA detection. The structural and physicochemical properties of the synthesized Zn2SnO4/PGO nanocomposite were systematically characterized using various spectroscopic techniques. Electrochemical studies, including electrochemical impedance spectroscopy (EIS), cyclic voltammetry (CV), and differential pulse voltammetry (DPV), demonstrated that the Zn2SnO4/PGO-modified electrode has a significantly enhanced electroactive surface area and efficient electron transport, resulting in superior electrocatalytic activity for 4-NBA detection. From the DPV quantification experiments, the limit of detection was calculated as 3.3 nM within the linear detection range of 0.1-231 mu M. The sensor demonstrated high accuracy, repeatability, reproducibility, and long-term stability. Anti-interference studies indicated no significant cathodic potential shifts in the presence of common interfering species. Finally, the Zn2SnO4/PGO-modified sensor was successfully applied to detect 4-NBA in real samples, including human urine, river water, and wastewater, showing excellent recovery rates. These findings confirm the sensor's potential for reliable and sensitive electrochemical monitoring of 4-NBA in different matrices, underscoring the importance of environmental safety and public health protections.

키워드