The physical properties of ultrathin transition
metal dichalcogenides (2D-TMDCs) make them promising candidates as active nanomaterials
for catalysis, optoelectronics, and biomedical applications. Chemical
modification of TMDCs is expected to be key in modifying/adding new functions
that will help make such promise a reality. We present a mild method for the modification
of the basal planes of 2H-MoS<sub>2</sub> and WS<sub>2</sub>. We exploit the
soft nucleophilicity of sulfur to react it with maleimide derivatives,
achieving covalent functionalization of 2H-TMDCs under very mild conditions.
Extensive characterization proves that the reaction occurs through Michael addition.
Our results adapt one of the most popular “click” reactions in polymer chemistry
and biochemistry to obtain a powerful tool for the chemical manipulation of
TMDCs.