Preparation of nickel oxide nanoparticles on N-doped reduced graphene oxide: A two-dimensional hybrid for electrocatalytic sensing of L-cysteine

A novel nickel oxide nanoparticles/N-doped reduced graphene oxide (NiO(x)NPs/N-rGO) nanocomposite was synthesized firstly. Scanning electron microscopy (SEM), transmission electron microscopy (TEM), Xray photoelectron spectroscopy (XPS) and electrochemical method were used to characterize the nanocomposite. The size of NiO(x)NPs was examined in the range from 20 to 50 nm. NiO(x)NPs/N-rGO modified carbon past electrode (CPE) was fabricated. NiO(x)NPs/N-rGO/CPE showed excellent electro-catalytic activity for the determination of L-cysteine in 0.1 M phosphate buffer (pH 10.0). Under the optimal conditions, the current response of L-cysteine increased linearly with its concentration from 0.3 to 1620.8 mu M, and the lowest detectable concentration was found to be 0.1 mu M. The material synthesis mechanism and electro-catalytic mechanism were proposed. (C) 2016 Elsevier B.V. All rights reserved.