Preparation and electrochemical performance of nano-silver-graphene composite by electroless plating

Abstract

Using glucose as the reducing agent, the nano-silver-graphene composite material (Ag/GR) was synthesized in situ by electroless plating, the structural morphology of the material was characterized and analyzed by X-ray diffraction (XRD), X-ray energy dispersive spectroscopy (EDS), X-ray photoelectron spectroscopy (XPS), scanning electron microscope (SEM) and Fourier infrared spectrometry (FTIR). The results show that the loading morphology of silver on the graphene surface is the single state that meets the expectation. The average particle size of AgNPs is about 21 nm. At the same time, the electrochemical response of ascorbic acid (AA) on Ag/GR/GCE electrochemical sensors was studied using the electrochemical test methods of cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS), linear sweep voltammetry (LSV) and differential pulse voltammetry (DPV). The electrochemical test results show that the Ag/GR composite has the highest response electrochemical signal of 212.9 μA and the lowest resistance of charge transfer of 90.5 Ω. The peak current is about twice that of the graphene electrode (110 μA) and about five times that of the glassy carbon electrode (42.5 μA). Due to the good synergistic effect of AgNPs and graphene, it has obvious electrocatalytic activity for AA. And the anode peak current and concentration show positive correlation linear change trend in the range of 5-120 μmol/L. However, the anode peak current of AA is highly correlated with the natural logarithm of the concentration range from 50 μmol/L to 120 μmol/L. The low limits of detection is 0.06 μmol/L.

Keywords

• electroless plating
• silver nanoparticle
• graphene
• ascorbic acid