Electrostatic Association of Ammonium-Functionalized Layered-Transition-Metal Dichalcogenides with an Anionic Porphyrin.

Ammonium-modified MoS and WS were prepared and characterized by complementary spectroscopic, thermal, and microscopic means. The positive charges on functionalized MoS and WS, due to the presence of ammonium units, were exploited to electrostatically bring in contact an anionic porphyrin bearing a carboxylate moiety, yielding porphyrin/MoS and porphyrin/WS ensembles, 5a and 5b, respectively. Efficient photoluminescence quenching of porphyrin's emission by MoS and WS within nanoensembles 5a and 5b, in combination with time-resolved photoluminescence assays, revealed transduction of energy from the photoexcited porphyrin to MoS or WS.