Using poly(m-aminobenzenesulfonic acid)-reduced MoS2 nanocomposite synergistic electrocatalysis for determination of dopamine

Abstract

Poly(m-aminobenzenesulfonic acid)-reduced MoS2 (PABSA-rMoS2) nanocomposites were prepared based on pre-obtained thin-layered MoS2 by pulse potentiostatic method (PPM). The thin-layered MoS2 as a scaffold was beneficial to the growth of PABSA because of its large and flat surface and the adsorption with m-ABSA. Using PPM, accompanied with the oxidative polymerization of m-ABSA at anodic potential, thin-layered MoS2 nanosheets were partly reduced at cathodic potential. The obtained PABSA-rMoS2 nanocomposites possessed large surface area, rich conjugated structure and negative charges that can easily adsorb positively charged aromatic compounds. As a model molecule, dopamine (DA) was chosen for studying the electrocatalytic property of PABSA-rMoS2 modified electrode. Experimental results showed that the electrochemical platform exhibited synergistic electrocatalytic activity for DA oxidation. Differential pulse voltammetry technique was applied for the trace detection of DA. Good linear relationship between DA concentration and peak current was displayed in the concentration range of 1–50μmolL−1 with a low detection limit of 0.22μmolL−1. It also displayed good selectivity, reproducibility and stability, and can be used in real sample analysis.