NiCo alloy nanoparticles anchored on polypyrrole/reduced graphene oxide nanocomposites for nonenzymatic glucose sensing
Abstract
NiCo alloy nanoparticles anchored on polypyrrole/reduced graphene oxide nanocomposites (NiCo/PPy/RGO) were successfully constructed through in situ chemical polymerization and a coreduction process for glucose sensing. Scanning electron microscopy (SEM), transmission electron microscopy (TEM), energy dispersive X-ray spectroscopy (EDS), X-ray diffraction (XRD) and Fourier transform infrared spectroscopy (FTIR) were employed to characterize the morphology and composition of NiCo/PPy/RGO. The electrochemical properties of the sensor were investigated by cyclic voltammetry and amperometry. The results indicated that the supporting substrate of PPy/RGO nanocomposites can provide a larger surface area for the dispersion of NiCo nanoparticles. Meanwhile, this nonenzymatic glucose sensor displayed an excellent electrocatalytic activity to glucose oxidation, with a low detection limit of 0.17 μM (S/N = 3), a linear range of 0.5 μM–4.1 mM, and a sensitivity of 153.5 μA mM−1 cm−2. The present study demonstrates that the NiCo/PPy/RGO composites are promising electroactive materials for developing non-enzymatic glucose sensors.