NiCo alloy nanoparticles anchored on polypyrrole/reduced graphene oxide nanocomposites for nonenzymatic glucose sensing

Abstract

The combination of PPy and graphene oxide was used as an effective supporting substrate for the loading of alloys.

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.