Thiol-functionalized single-layered MoS2 nanosheet as a photoluminescence sensing platform via charge transfer for dopamine detection

Novel fluorescent thioglycollic acid (TGA) surface-functionalized single-layered thickness structured MoS 2 nanosheets were purposely synthesized by a facile one-step hydrothermal treatment of using molybdenyl acetylacetonate, TGA and sodium sulfide as precursors. During the process of synthesis, we subtly solved the problem of the poor water solubility of the precursor molybdenyl acetylacetonate, and obtained thiolated single-layer MoS 2 nanosheet (TGA-MoS 2 ) with excellent water solubility and stable fluorescence property. The fluorescence of TGA-modified MoS 2 nanosheets was significantly suppressed in the presence of dopamine (DA), and a simple sensing system for highly selective, fast, direct detection of dopamine was established. Meanwhile, the present methodology has a wide detection range of 0.05   μΜ to 20   μΜ, a comparable detection limit of 27   nM and an extremely short response time of 3   min. To understand the fast response behavior, we tried effort to explain the interaction mechanisms between TGA-MoS 2 nanosheets and the quencher DA. Further research suggests that the possible mechanism might be the charge transfer (CT) by the stacking of MoS 2 layers through C O⋯H O hydrogen boding interaction, providing a fast fluorescence sensing platform for DA determination in urine and serum sample.