Hierarchical molybdenum dichalcogenide nanosheets assembled nitrogen doped graphene layers for sensitive electrochemical dopamine detection

Highlights: • A novel sensor of hierarchical MoS₂ NSs/N-Gr nanohybrid was facilely synthesized. • The sensor demonstrated highly electrocatalytic activity for dopamine detection. • The sensor showed linear range of 3.2 μM–5.68 mM and low detection limit of 11.9 μM. • The sensor showed very fast response of 1.5 s and excellent selectivity. • The sensor showed accurate detection of dopamine in real human blood samples. -- Abstract: In present work, we proposed a novel nanohybrid based on hierarchical molybdenum dichalcogenide nanosheets uniformly assembled over surface of nitrogen-doped graphene (MoS₂ NSs/N-Gr) via a facile and cost-effective synthesis approach. The developed material was applied for highly sensitive dopamine (DA) detection. It was demonstrated that the MoS₂ NSs/N-Gr nanohybrids displayed excellent sensitivity towards DA sensing with an outstanding detection range of 3.2 μM–5.68 mM, low detection limit of 11.9 μM (S/N = 3), and very fast response (~1.5 s). In addition, the proposed sensor also exhibited long-term stability and good selectivity for the target analyte. Remarkably, it can successfully perform accurate detection of DA in human blood serum samples. Therefore, the results suggest that such nanohybrid-based sensor may be a potential candidate for electrochemical detection of DA in practical analysis.