MnO₂ Nanowires-Decorated Reduced Graphene Oxide Modified Glassy Carbon Electrode for Sensitive Determination of Bisphenol A

Abstract

In this paper, MnO2 nanowires-decorated reduced graphene oxide composite (MnO2 NWs-rGO) was synthesized by physical adsorption and controlled potential reduction. Means of X-ray diffraction (XRD), scanning electron microscopy (SEM), and cyclic voltammetry (CV) were used to characterize this material. Glassy carbon electrode (GCE) modified with MnO2 NWs-rGO composite was fabricated by drop-coating method for the sensitive determination of bisphenol A (BPA). Electrochemical behaviors of BPA at the MnO2 NWs-rGO/GCE were studied using CV and chronocoulometry (CC). Experimental results found that MnO2 NWs-rGO/GCE exhibited excellent electrocatalytic activity, sensitivity, stability, and selectivity towards BPA. Under the optimized experimental conditions, quantitative analysis was carried out using the second derivative linear sweep voltammetry (SDLSV), and the MnO2 NWs-rGO/GCE revealed a good linear response to BPA concentration ranging from 0.02–20 μM and 20–100 μM, and the detection limit was 6.0 nM (S/N = 3). This new method possessed some obvious advantages, such as high determination sensitivity, simple preparation process, rapid response and low cost. The sensing performance of MnO2 NWs-rGO/GCE was demonstrated for the detection of BPA in plastic samples, and satisfactory results have been obtained. Therefore, an efficient determination method for monitoring trace levels of BPA was developed.