Determination of Bisphenol A in Beverages by an Electrochemical Sensor Based on Rh2O3/Reduced Graphene Oxide Composites

A novel electrochemical sensor, based on a Rh2O3–reduced graphene oxide (rGO) composite modified carbon electrode, has been developed for detecting bisphenol A (BPA) in beverages. The prepared Rh2O3/rGO and its precursor materials were characterized by scanning electron microscope (SEM) and X-ray diffraction (XRD). Under optimum conditions, the sensor presented good electrochemical performance for analyzing BPA, with a linear range of 0.6–40 μM, detection limit of 0.12 μM, good reproducibility, and excellent stability. The good performance can be attributed to the combination of the good catalytic properties of Rh2O3 and good conductivity of rGO. The sensor is directly used for detecting BPA in the residual solutions of four beverages after simple filtration, with satisfactory recoveries of 93–99%.