Facile Synthesis of Au/Ni(OH)2 Nanocomposites and its Application in Nonenzymatic Glucose Sensing

A simple and environment-friendly autocatalytic reduction process was developed for synthesis of Au/Ni(OH)2 nanocomposites. The nanocomposites were characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS). It is found the nanocomposites are composed of ultrathin Ni(OH)2 nanosheets and gold nanoparticles (AuNPs), and the AuNPs disperse evenly on the Ni(OH)2 nanosheets. The electrochemical and electrocatalytic properties of the Au/Ni(OH)2 modified glassy carbon electrode (Au/Ni(OH)2/GCE) were investigated by electrochemical experiments. Furthermore, through optimizing Au loading of the nanocomposites, the 5%-Au/Ni(OH)2/GCE displays the best electrocatalytic activity towards glucose oxidization in alkaline medium. Under optimal conditions, the 5%-Au/Ni(OH)2/GCE displays a wide linear range of 0.01 to 3.15 mM (R2 = 0.998) to glucose. Besides, the sensor has a low detection limit of 0.10 μM (S/N = 3) and a high sensitivity of 342.1 μA·mM−1·cm−2. It also displays satisfying stability, good reproducibility and selectivity.