Preparation of gold decorated MoS2/NiO nanocomposite in the production of a new electrochemical sensor for ascorbic acid detection

Abstract

We investigated electrochemical sensing of ascorbic acid by Au-MoS2/NiO modified glassy carbon electrode. The MoS2, NiO, MoS2/NiO were prepared by hydrothermal, and Au-MoS2/NiO was prepared chemical reduction method. The characterization of Au-MoS2/NiO composite was carried out using X-ray diffraction, Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy and field emission scanning electron microscopy. The electrochemical characteristics of the Au-MoS2/NiO composite were examined by cyclic voltammetry and electrochemical impedance spectroscopy. Then, differential pulse voltammetry responses of Au-MoS2/NiO modified glassy carbon electrode were detected towards the ascorbic acid in phosphate buffer (0.1 M, pH=7). The ascorbic acid sensor represented low detection limit of 0.13 mu M with linear range of 2-50 mu M, revealing that this sensor gave satisfactory responses. The practical feasibility of the obtained sensor was assessed for the detection of ascorbic acid in Vitamin C tablet. We believe that this study could help different studies for producing commercially ascorbic acid sensors.