Abstract
Liquid Phase Exfoliation (LPE) is a common route to produce two-dimensional MoS2 nanosheets. In this research, MoS2 powder is exfoliated by an ultrasonic probe (sonicator) in a water-ethanol solution. It is reported that MoS2 as a prototype 2D Transition Metal Dichalcogenide, has a band gap that increases with a decreasing number of layers. There are some factors that affect the average band gap energy value and the thickness of the exfoliated flakes. We varied different parameters of the ultrasonic probe like power, pulse percentage and time duration of sonication to investigate the effects on the number of MoS2 layers. Our findings from the UV-Visible spectra, SEM, FESEM and TEM images indicate that the minimum thickness for these samples was acquired at 50% of the input power of the sonicator we used (65 W) and the optimum pulse percentage is 50%. The current study also found that the average amount of band gap increased with an increase in sonication time, and then remained unchanged after 60 minutes.Keywords:
ultrasonic probe, 2D MoS2 band gap, power output, pulse percentage, sonication timeReferences
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51. Zhu J. et al. (2016), Thickness-dependent bandgap tunable molybdenum disulfide films for optoelectronics, RSC Advances, 6: 110604–110609, https://doi.org/10.1039/C6RA22496B
2. Backes C. et al. (2014), Edge and confinement effects allow in situ measurement of size and thickness of liquid-exfoliated nanosheets, Nature Communications, 5: 4576, https://doi.org/10.1038/ncomms5576
3. Backes C. et al. (2017), Guidelines for exfoliation, characterization and processing of layered materials produced by liquid exfoliation, Chemistry of Materials, 29(1): 243–255, https://doi.org/10.1021/acs.chemmater.6b03335
4. Backes C. et al. (2020), Production and processing of graphene and related materials, 2D Materials, 7(2): 022001, https://doi.org/10.1088/2053-1583/ab1e0a
5. Bang J.H., Suslick K.S. (2010), Applications of ultrasound to the synthesis of nanostructured materials, Advanced Materials, 22(10): 1039–1059. https://doi.org/10.1002/adma.200904093
6. Bari R. et al. (2015), Liquid phase exfoliation and crumpling of inorganic nanosheets, Physical Chemistry Chemical Physics, 17(14): 9383–9393, https://doi.org/10.1039/C5CP00294J
7. Brent J.R., Savjani N., O'Brien P. (2017), Synthetic approaches to two-dimensional transition metal dichalcogenide nanosheets, Progress in Materials Science, 89: 411–478, https://doi.org/10.1016/j.pmatsci.2017.06.002
8. Brotchie A., Grieser F., Ashokkumar M. (2009), Effect of power and frequency on bubble-size distributions in acoustic cavitation, Physical Review Letters, 102(8): 084302, https://doi.org/10.1103/physrevlett.102.084302
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12. Coleman J.N. et al. (2011), Two-dimensional nanosheets produced by liquid exfoliation of layered materials, Science, 331(6017): 568–571, https://doi.org/10.1126/science.1194975
13. Connors K.A., Wright J. (1989), Dependence of surface tension on composition of binary aqueous-organic solutions, Analytical Chemistry, 61(3): 194–198, https://doi.org/10.1021/ac00178a001
14. Ebrahiminia A., Mokhtari-Dizaji M., Toliyat T. (2013), Correlation between iodide dosimetry and terephthalic acid dosimetry to evaluate the reactive radical production due to the acoustic cavitation activity, Ultrasonics Sonochemistry, 20: 366–372, https://doi.org/10.1016/j.ultsonch.2012.05.016
15. Frisenda R. et al. (2016), Micro-reflectance and transmittance spectroscopy: A versatile and powerful tool to characterize 2D materials, Journal of Physics D: Applied Physics, 50(7): 074002, https://doi.org/10.1088/1361-6463/aa5256
16. Ghasemi F., Mohajerzadeh S. (2016), Sequential solvent exchange method for controlled exfoliation of MoS2 suitable for phototransistor fabrication, ACS Applied Materials & Interfacesaces, 8 (45): 31179–31191, https://doi.org/10.1021/acsami.6b07211
17. Hajnorouzi A., Afzalzadeh R., Ghanati F. (2014), Studies on the regularity of wave intensity in ultrasonic bath and spherical reactor, Journal of Acoustical Engineering Society of Iran, 2(1): 32–39.
18. Han J.T. et al. (2014), Extremely efficient liquid exfoliation and dispersion of layered materials by unusual acoustic cavitation, Scientific Reports, 4(1): 5133, https://doi.org/10.1038/srep05133
19. Han S.A., Bhatia R., Kim S-W. (2015), Synthesis, properties and potential applications of two-dimensional transition metal dichalcogenides, Nano Convergence, 2(1): 17, https://doi.org/10.1186/s40580-015-0048-4
20. Huo C., Yan Z., Song X., Zeng H. (2015), 2D materials via liquid exfoliation: a review on fabrication and applications, Science Bulletin, 60(23): 1994–2008, https://doi.org/10.1007/s11434-015-0936-3
21. Jawaid A. et al. (2016), Mechanism for liquid-phase exfoliation of MoS2, Chemistry of Materials, 28(1): 337–348, https://doi.org/10.1021/acs.chemmater.5b04224
22. Kajbafvala M., Farbod M. (2018), Effective size selection of MoS2 nanosheets by a novel liquid cascade centrifugation: Influence of the flakes dimensions on electrochemical and photoelectrochemical applications, Journal of Colloid and Interface Science, 527: 159–171, https://doi.org/10.1016/j.jcis.2018.05.026
23. Kiełczyński P., Ptasznik S., Szalewski M., Balcerzak A., Wieja K., Rostocki A.J. (2019), Application of ultrasonic methods for evaluation of high-pressure physicochemical parameters of liquids, Archives of Acoustics, 44(2): 329–337, https://doi.org/10.24425/aoa.2019.128496
24. Kudryashova O.B., Vorozhtsov A., Danilov P. (2019), Deagglomeration and coagulation of particles in liquid metal under ultrasonic treatment, Archives of Acoustics, 44(3), 543–549, https://doi.org/10.24425/aoa.2019.129269
25. Liu Y.D. et al. (2013), Preparation, characterization and photoelectrochemical property of ultrathin MoS2 nanosheets via hydrothermal intercalation and exfoliation route, Journal of Alloys and Compounds, 571: 37–42, https://doi.org/10.1016/j.jallcom.2013.03.031
26. Mak K.F., Lee C., Hone J., Shan J., Heinz T.F. (2010), Atomically thin MoS2: A new direct-gap semiconductor, Physical Review Letters, 105(13): 136805, https://doi.org/10.1103/physrevlett.105.136805
27. Marcus Y. (2018), Extraction by subcritical and supercritical water, methanol, ethanol and their mixtures, Separations, 5(1): 4, https://doi.org/10.3390/separations5010004
28. Mas-Ballesté R., Gómez-Navarro C., J. Gómez–Herrero, Zamora F. (2011), 2D materials: to graphene and beyond, Nanoscale, 3(1): 20–30, https://doi.org/10.1039/C0NR00323A
29. Merouani S., Hamdaoui O., Rezgui Y., Guemini M. (2013), Effects of ultrasound frequency and acoustic amplitude on the size of sonochemically active bubbles – theoretical study, Ultrasonics Sonochemistry, 20(3): 815–819, https://doi.org/10.1016/j.ultsonch.2012.10.015
30. Miró P., Audiffred M., Heine T. (2014), An atlas of two-dimensional materials, Chemical Society Reviews, 43(18): 6537–6554, https://doi.org/10.1039/C4CS00102H
31. Nguyen E.P. et al. (2015), Investigation of two-solvent grinding-assisted liquid phase exfoliation of layered MoS2, Chemistry of Materials, 27(1): 53–59, https://doi.org/10.1021/cm502915f
32. Nguyen T.P., Sohn W., Oh J.H., Jang H.W., Kim S.Y. (2016), Size-dependent properties of two-dimensional MoS2 and WS2, The Journal of Physical Chemistry C, 120(8): 10078–10085, https://doi.org/10.1021/acs.jpcc.6b01838
33. Nicolosi V., Chhowalla M., Kanatzidis M.G., Strano M.S., Coleman J.N. (2013), Liquid exfoliation of layered materials, Science, 340(6139): 1226419-(1–18), https://doi.org/10.1126/science.1226419
34. Niu Y. et al. (2018), Thickness-dependent differential reflectance spectra of monolayer and few-layer MoS2, MoSe2, WS2 and WSe2, Nanomaterials, 8(9): 725, https://doi.org/10.3390/nano8090725
35. Peng J., Weng J. (2015), One-pot solution-phase preparation of a MoS2/graphene oxide hybrid, Carbon, 94: 568–576. https://doi.org/10.1016/j.carbon.2015.07.035
36. Pokhrel N., Vabbina P.K., Pala N. (2016), Sonochemistry: Science and Engineering, Ultrasonics Sonochemistry, 29: 104–128, https://doi.org/10.1016/j.ultsonch.2015.07.023
37. Qiao W. et al. (2014), Effects of ultrasonic cavitation intensity on the efficient liquid-exfoliation of MoS2 nanosheets, RSC Advances, 4(92): 50981–50987, https://doi.org/10.1039/C4RA09001B
38. Samadi M., Sarikhani N., Zirak M., Zhang H., Zhang H-L., Moshfegh A.Z. (2018), Group 6 transition metal dichalcogenide nanomaterials: synthesis, applications and future perspectives, Nanoscale Horizons, 3(2): 90−204, https://doi.org/10.1039/C7NH00137A
39. Shen J. et al. (2015), Liquid phase exfoliation of two-dimensional materials by directly probing and matching surface tension components, Nano Letters, 15(8): 5449–5454, https://doi.org/10.1021/acs.nanolett.5b01842
40. Song X., Hub J., Zeng H. (2013), Two-dimensional semiconductors: recent progress and future perspectives, Journal of Materials Chemistry C, 1(17): 2952–2969, https://doi.org/10.1039/C3TC00710C
41. Tamura R., Miyata M. (Eds) (2015), Advances in Organic Crystal Chemistry: Comprehensive Reviews, Springer, https://doi.org/10.1007/978-4-431-55555-1
42. Tonndorf P. et al. (2013), Photoluminescence emission and Raman response of monolayer MoS2, MoSe2, and WSe2, Optics Express, 21(4): 4908–4916, https://doi.org/10.1364/OE.21.004908
43. Vella D. et al. (2016), Femtosecond spectroscopy on MoS2 flakes from liquid exfoliation: surfactant independent exciton dynamics, Journal of Nanophotonics, 10(1): 012508-1–012508-8. https://doi.org/10.1117/1.JNP.10.012508
44. Voshell A., Terrones M., Rana M. (2018), Review of optical properties of two-dimensional transition metal dichalcogenides, Proceedings of SPIE 10754, Wide Band gap Power and Energy Devices and Applications III, 107540L, https://doi.org/10.1117/12.2323132
45. Wang F. et al. (2015), Synthesis, properties and applications of 2D non-graphene materials, Nanotechnology, 26(29): 292001, https://doi.org/10.1088/0957-4484/26/29/292001
46. Wang Q.H, Kalantar-Zadeh K., Kis A., Coleman J.N., Strano M.S. (2012), Electronics and optoelectronics of two-dimensional transition metal dichalcogenides, Nature Nanotechnology, 7(11): 699–712, https://doi.org/10.1038/nnano.2012.193
47. Wang Z.M. (2014), MoS2-Materials, Physics, and Devices. Lecture Notes in Nanoscale Science and Technology, Vol. 21, Springer International Publishing, Switzerland, https://doi.org/10.1007/978-3-319-02850-7
48. Xu H., Zeiger B.W., Suslick K.S. (2013), Sonochemical synthesis of nanomaterials, Chemical Society Reviews, 42(7): 2555–2567, https://doi.org/10.1039/C2CS35282F
49. Yang L. et al. (2018), Properties, preparation and applications of low dimensional transition metal dichalcogenides, Nanomaterials, 8(7): 463, https://doi.org/10.3390/nano8070463
50. Zhang G., Liu H., Qu J., Li J. (2016), Two-dimensional layered MoS2: rational design, properties and electrochemical applications, Energy & Environmental Science, 9: 1190–1209, https://doi.org/10.1039/C5EE03761A
51. Zhu J. et al. (2016), Thickness-dependent bandgap tunable molybdenum disulfide films for optoelectronics, RSC Advances, 6: 110604–110609, https://doi.org/10.1039/C6RA22496B
