The Synthesis of rGO/Ni/Co Composite and Electrochemical Determination of Dopamine

Abstract

In this paper, a composite material (rGO/Ni/Co) was synthesized by a hydrothermal method and high temperature annealing, and used for the determination of dopamine (DA). Surface morphology and structure of the rGO/Ni/Co were characterized by Scanning electron microscope (SEM), Transmission electron microscope (TEM), Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD). The effects of different pH, scanning rate and interfering substances on the electrochemical properties of dopamine were discussed. The electrochemical test results show that the rGO/Ni/Co/GCE electrode has excellent electrocatalytic activity for dopamine. Under the optimized conditions, the linear range of detection is 10 µmol/L-2250 µmol/L (r = 0.99837), the detection limit is 0.119 µmol/L, and the signal-to-noise ratio is 3. The interference test showed, that most of the ions did not show obvious influence on the detection of DA, indicating that the prepared electrode has selectivity for the detection of DA. Moreover, the composite has good magnetic properties and is convenient for sample separation and recovery.