A sensitive electrochemical sensor for catechol detection based on reduced graphene oxide
摘要
The environmental pollution caused by phenolic pollutants has attracted more and more attention, and developing simple and efficient detection methods for phenolic pollutants has aroused great interest of researchers. In this paper, a reduced graphene oxide (RGO)-modified electrode with high electrocatalytic activity was prepared by simple electrochemical reduction of graphene oxide (GO) on a glassy carbon electrode using cyclic voltammetry. The electrode-modified materials were systematically characterized by UltraViolet–Visible (UV–Vis), Fourier transform infrared spectroscopy (FTIR), field emission scanning electron microscopy (FE-SEM), X-ray diffraction spectroscopy (XRD) and electrochemical impedance spectroscopy (EIS). Differential pulse voltammetry (DPV) was employed to detect catechol with high sensitivity. The effects of conditions such as the amount of GO suspension, cycle number of cyclic voltammetry reduction, pH value of the buffer solution, and accumulation time on the detection of catechol were investigated. Under optimal conditions, the oxidation peak current of catechol showed a good linear relationship with its concentration when the concentration of catechol was in the range of 1 × 10−7 M ~ 1 × 10−5 M. The linear equation was expressed as I (μA) = 2.1321 C (μM) + 4.2807 with a correlation coefficient of 0.9902, and the limit of detection (LOD) was 4.5 × 10−8 M. Meanwhile, this electrochemical sensor has been proven to be applicable for the determination of catechol in an actual water sample.