Electrochemical sensing based on layered MoS2–graphene composites

Layered MoS2–graphene composites were synthesized by a modified l-cysteine-assisted solution-phase method, and were characterized by X-ray diffraction (XRD), field emission scanning electron microscopy (SEM), and high-resolution transmission electron microscopy (TEM). The electrochemical properties of the nanocomposite film were investigated by electrochemical impedance spectroscopy (EIS) and cyclic voltammetry (CV). Acetaminophen as model molecular was employed to study its electrochemical responses at the MoS2–graphene modified electrode, which shows more favorable electron transfer kinetics than graphene modified glassy carbon and bare glassy carbon electrodes. This novel electrochemical sensor exhibits excellent analytical performance for acetaminophen detection with detection limit of 2.0 × 10−8 M (S/N = 3) and linear range of 0.1–100 μM. The superior electrochemical performances of MoS2–graphene composites are attributed to their robust composite structure and the synergistic effects between layered MoS2 and graphene, and it may hold great promise for electrochemical sensors and biosensors design.