posted on 2021-06-02, 18:39authored byChang-Seuk Lee, Tae Hyun Kim
With
their similar layered structures and complementary physicochemical
properties, molybdenum disulfide (MoS<sub>2</sub>) and graphene nanosheets
can be formed into MoS<sub>2</sub>/graphene heterostructures with
improved electrical, optical, catalytic, and electrochemical properties,
enabling promising applications. Here, we present a method to prepare
MoS<sub>2</sub>/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.
MoS<sub>2</sub>/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 MoS<sub>2</sub> to graphite. Optimum conditions are
achieved by comparing the graphene concentration produced, <i>I</i><sub>D</sub>/<i>I</i><sub>G</sub>, <i>I</i><sub>2D</sub>/<i>I</i><sub>G</sub>, and E<sub>2g</sub>–A<sub>1g</sub> 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
MoS<sub>2</sub>/graphene nanocomposites to highly sensitive electrochemical
sensors. When used to modify an electrode for electrochemical sensing,
the MoS<sub>2</sub>/graphene nanocomposites exhibit excellent electrochemical
performances in the detection of morin.