Tuning the optical emission of MoS2 nanosheets using proximal photoswitchable azobenzene molecules
Articolo
Data di Pubblicazione:
2014
Citazione:
Tuning the optical emission of MoS2 nanosheets using proximal photoswitchable azobenzene molecules / J. Li, J. Wierzbowski, Ö. Ceylan, J. Klein, F. Nisic, T. Le Anh, F. Meggendorfer, C. Palma, C. Dragonetti, J.V. Barth, J.J. Finley, E. Margapoti. - In: APPLIED PHYSICS LETTERS. - ISSN 0003-6951. - 105:24(2014), pp. 241116.1-241116.6. [10.1063/1.4904824]
Abstract:
We report photoluminescence measurements performed on monolayer- and two-layer-MoS2 placed on two types of mixed self-assembled monolayers (mSAMs) of photoswitchable azobenzene molecules. The two mSAMs differ via the electronegative character of the azobenzene derivatives. Thin layers of a transition metal dichalcogenide - MoS2 - were mechanically exfoliated on mSAM to allow for direct interaction between the molecules and the MoS2 layers. When the MoS2 nanosheet is in contact with the electropositive azobenzene molecules in trans configuration, an emission side band at lower energies and at low excitation powers suggest n-type doping. The photoisomerization of the molecules from trans to cis configuration lowers the doping, quenching the side band and enhancing the overall PL efficiency by a factor of ∼3. Opposite results were observed with the chlorinated, more electronegative molecules, exhibiting a reversed trend in the PL efficiency between trans and cis, but with an overall larger intensity. The type of doping induced by the two types of mSAMs was determined by Kelvin probe force microscopy technique.
Tipologia IRIS:
01 - Articolo su periodico
Keywords:
physics and astronomy (miscellaneous)
Elenco autori:
J. Li, J. Wierzbowski, Ö. Ceylan, J. Klein, F. Nisic, T. Le Anh, F. Meggendorfer, C. Palma, C. Dragonetti, J.V. Barth, J.J. Finley, E. Margapoti
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