Determination of catechol and hydroquinone with high sensitivity using MOF-graphene composites modified electrode

Abstract A composite (MOF-GO) of Cu-based MOF-199 (MOF) and graphene oxide (GO) was prepared by the solvothermal method and used as the modified material to fabricate an electrochemical sensor for the determination of catechol (CT) and hydroquinone (HQ). The modification was carried out through the electrodeposition of MOF-GO composites on the glassy carbon electrode and the transformation of MOF-GO to MOF-ERGO by an electrochemical reduction. Differential pulse voltammetry (DPV) was employed for exploring the electrochemical properties of the as-prepared electrode and the oxidation of CT and HQ at the modified electrode. Under the optimized experimental condition, the linear calibration curve was obtained in the range from 0.1 μM to 566 μM for CT ( R 2  = 0.997) and 0.1 μM to 476 μM for HQ ( R 2  = 0.999) with the same low detection limit of 0.1 μM ( S / N  = 3). The experimental results showed that the modified electrode was easily fabricated in control and exhibited the outstanding stability. The validity for practical samples detection of CT and HQ was also demonstrated with satisfactory results.