Large-Scale Preparation of MoS₂/Graphene Composites for Electrochemical Detection of Morin

With their similar layered structures and complementary physicochemical properties, molybdenum disulfide (MoS₂) and graphene nanosheets can be formed into MoS₂/graphene heterostructures with improved electrical, optical, catalytic, and electrochemical properties, enabling promising applications. Here, we present a method to prepare MoS₂/graphene nanocomposites by liquid-phase exfoliation through the combined processes of high shear mixing and ultrasonication in deionized water without additional additives, under ambient conditions. MoS₂/graphene nanocomposites in large quantities can be achieved with a high-speed mixer homogenizer and a tip sonicator by optimizing the processing parameters for shear exfoliation, such as shearing speed, shearing time, ultrasonication time, and the weight ratio of bulk MoS₂ to graphite. Optimum conditions are achieved by comparing the graphene concentration produced, I_D/I_G, I_2D/I_G, and E_2g–A_1g values from the Raman spectra. This is an easily available and facile method, thereby rendering it an efficient route for large-scale industrial production. We also demonstrate the application of the MoS₂/graphene nanocomposites to highly sensitive electrochemical sensors. When used to modify an electrode for electrochemical sensing, the MoS₂/graphene nanocomposites exhibit excellent electrochemical performances in the detection of morin.