A one-step approach to the large-scale synthesis of functionalized MoS₂nanosheets by ionic liquid assisted grinding

Abstract

A prerequisite for exploiting most proposed applications for MoS2 is the availability of water-dispersible functionalized MoS2 nanosheets in large quantities. Here we report one-step synthesis and surface functionalization of MoS2 nanosheets by a facile ionic liquid assisted grinding method in the presence of chitosan. The selected ionic liquid with suitable surface energy could efficiently overcome the van der Waals force between the MoS2 layers. Meanwhile, chitosan molecules bind to the plane of MoS2 sheets non-covalently, which prevents the reassembling of exfoliated MoS2 sheets and facilitates the exfoliation progress. The obtained chitosan functionalized MoS2 nanosheets possess favorable stability and biocompatibility, which renders them as promising and biocompatible near-infrared agents for photothermal ablation of cancer. This contribution provides a facile way for the green, one-step and large-scale synthesis of advanced functional MoS2 materials.

Emerging Trends in Phosphorene Fabrication towards Next Generation Devices

“…ILs are presented by researchers for efficient exfoliation of 2D materials to obtain a stable yield with a high concentration of the suspended nanoflakes 200, 201, 202, 203. ILs exhibit viscosities that are 1−3 orders of magnitude more than those of conventional organic solvents; this influences the rate of mass transport within the solution by preventing the BP nanosheets from restacking 198, 200.…”

“…An environmentally friendly liquid exfoliation by means of ionic liquids was reported by Zhao et al200 to exfoliate highly pure, crystalline, atomic‐scale and uniform mono‐ to few‐layer BP nanosheets by mild grinding and weak sonication. The first step in IL‐exfoliation was grinding bulk BP (30 mg) with ILs (0.5 mL) for 20 min using an agate mortar with a pestle that supplements the mechanical shear forces to reduce the exfoliation time due to the increase in the surface area of BP 118, 182, 203. The next step was to disperse the mixtures in ILs (3 mg mL −1 BP) by ice‐bath sonication (100 W) for 24 h to obtain suspensions of BP flakes which were further centrifuged at 4000 rpm for 45 min to remove the unexfoliated BP.…”

Ionic strength induced electrodeposition of two-dimensional layered MoS 2 nanosheets

“…The other two broad peaks located at 463 nm and 407 nm are associated with the transitions between the higher densities of state region [27]. The presence of characteristic peaks (A 1 and B 1 ) reveals the successful exfoliation of MoS 2 into few layered nanosheets [6,27,28]. The stability of the colloid is verified when the same PAA-MoS 2 dispersion is analysed under UV-vis after two weeks (Fig.…”

“…The two peaks observed at 677 nm (A 1 ) and 617 nm (B 1 ) are associated with the interlayer interaction and spin-orbit splitting of Mo 4d and S 3p orbitals [6]. The other two broad peaks located at 463 nm and 407 nm are associated with the transitions between the higher densities of state region [27]. The presence of characteristic peaks (A 1 and B 1 ) reveals the successful exfoliation of MoS 2 into few layered nanosheets [6,27,28].…”

Dispersible MoS2 micro-sheets induced a proinflammatory response and apoptosis in the gills and liver of adult zebrafish

“…20 In short, 250 mg of bulk MoS 2 powder (99.995%, Sigma-Aldrich, USA) was ground with 100 mg of chitosan (CS) (Sigma-Aldrich, USA) for 10 min using an agate mortar and a pestle. 0.5 mL of BMIPF6 (1-butyl-3-methylimidazolium hexauorophosphate, $97.0%, Shanghai Chengjie Chemical Company, China) was then added into the mortar, and the mixture was ground for another 50 min.…”