10.1002/asia.201701199
Chemistry - An Asian Journal
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Figure 7. a) Optimized structure of the partial framework of a MoS2 nanosheet
interacted with dispersant 1b. b) Fluorescence spectra (NMP, λex = 369 nm,
r.t., 0.44 mM based on 1b) of dispersant 1b and MoS2 nanocomposite 3b.
In conclusion, we have revealed that V-shaped
polyaromatic compounds bearing three non-ionic side chains
(i.e., 2-methoxyethoxy groups) act as new dispersants for
inorganic MoS2 nanosheets in NMP. The V-shaped dispersants
newly designed in this work are readily synthesized in four-step
reactions. Manual grinding and sonication (within total 1 h) of
bulk MoS2 in the presence of the dispersant afford highly
dispersed MoS2 nanosheets. Notably, the lateral sizes and
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hydrophobic interactions are essential for the formation of the
highly dispersed nanosheets. With the aid of the present facile
and reliable method, the dispersion of other layered inorganic
compounds (e.g., WS2 and h-BN nanosheets) for the
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Acknowledgements
(138.6º) upon stack with
a
MoS2 nanosheet due to strong
This work was supported by JSPS KAKENHI, Grant No.
JP25104011 and JP26288033, and “Support for Tokyotech
Advanced Researchers (STAR)”. We thank Dr. Takayuki Arai
(JSR Corporation) for the initial synthesis of compounds 5a,b
and studies on their host properties. We also thank Dr. Yuka
Akimoto and Mr. Yoshiyuki Satoh (Tokyo Institute of
Technology) for the FE-SEM analysis.
intermolecular interactions. The grinding process most probably
prompts the intermolecular stacks (Figure 1c).
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Keywords: interactions, polyaromatic ring, MoS2, dispersion,
nanosheets
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methanol to remove hydrophilic 1b to give pure MoS2 nanosheets (0.31
mg), which show no emission derived from fluorescent 1b.
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mg/mL in NMP after centrifugation at 1,500 rpm)[4b] because of using
high-speed centrifugation (14,800 rpm) for the purification.
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S22).[15]
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