Fabrication of Au Nanoparticle-Decorated MoS2 Nanoslices as Efficient Electrocatalysts for Electrochemical Detection of Dopamine

Chen Chen,Hong Hong

doi:10.3390/catal9080653

Abstract

Herein, MoS2 nanoslices were simply prepared by using ultrasonic treatment, and were further decorated with Au nanoparticles (AuNPs) through an electrodeposition process to obtain the MoS2/Au nanocomposites. The obtained nanocomposites display synergetic electrocatalytic effect for the oxidation of dopamine due to the large surface area and two-dimensional structure of the MoS2 nanoslices, combining with the high catalytic activity and good conductivity of AuNPs. An electrochemical sensor was constructed based on MoS2/Au-modified carbon paste electrode, for sensitive and quantitative determination of dopamine. The prepared electrochemical sensor proves excellent analytical performances: very high sensitivity, wide linear ranges (0.5–300 μM), and low detection limit (76 nM). Moreover, the dopamine sensor also displays high selectivity, good reproducibility and stability, and can be used in real sample analysis. The method of fabricating high-efficiency electrocatalysts and electrochemical sensors proposed in this study provides a good reference for developing more functionalized nanocomposites and for extending practical applications.

Highlights

Dopamine (DA) is a kind of key neurotransmitter, which plays an important role in the normal operation of multiple systems of human body [1,2,3]
Yang et al [16] reported an electrochemical sensor for DA detection based on electrochemically reduced graphene oxide, which showed a low detection limit of 0.5 μM
The morphologies of MoS2 nanoslices and MoS2 /Au nanocomposites were characterized by scanning electron microscopy (SEM) and transmission electron microscopy (TEM)

Summary

Introduction

Dopamine (DA) is a kind of key neurotransmitter, which plays an important role in the normal operation of multiple systems of human body [1,2,3]. Of the various methods of DA determination [2,5,6], the electrochemical sensor is preferred due to its fast response, high sensitivity, good selectivity, and low cost [7,8]. In order to get better response signals, various nanomaterials or nanocomposites have been used as electrocatalysts towards the oxidation of DA, such as carbon-based nanomaterials, noble metal nanoparticles [9], and conducting polymers [3,10,11,12]. Among these materials, two-dimensional (2D) nanomaterials or their corresponding composites play major roles. Taylor et al [17] demonstrated that poly(3,4-ethylene dioxythiophene)/graphene oxide as electrode modifying material could increase the sensitivity and decrease the detection limit for the electrochemical detection of DA

Methods

Discussion

Conclusion