Universal mechanical exfoliation of large-area 2D crystals

Abstract

Two-dimensional materials provide extraordinary opportunities for exploring phenomena arising in atomically thin crystals. Beginning with the first isolation of graphene, mechanical exfoliation has been a key to provide high-quality two-dimensional materials, but despite improvements it is still limited in yield, lateral size and contamination. Here we introduce a contamination-free, one-step and universal Au-assisted mechanical exfoliation method and demonstrate its effectiveness by isolating 40 types of single-crystalline monolayers, including elemental two-dimensional crystals, metal-dichalcogenides, magnets and superconductors. Most of them are of millimeter-size and high-quality, as shown by transfer-free measurements of electron microscopy, photo spectroscopies and electrical transport. Large suspended two-dimensional crystals and heterojunctions were also prepared with high-yield. Enhanced adhesion between the crystals and the substrates enables such efficient exfoliation, for which we identify a gold-assisted exfoliation method that underpins a universal route for producing large-area monolayers and thus supports studies of fundamental properties and potential application of two-dimensional materials.

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References 55

1. 1.

   He SL, et al. Phase diagram and electronic indication of high-temperature superconductivity at 65 K in single-layer FeSe films. Nat. Mater. 2013;12:605-610.

   Not in our library10.1038/nmat3648

2. 2.

   Zhang C, et al. Engineering point-defect states in monolayer WSe2. ACS Nano. 2019;13:1595-1602.

   Not in our library10.1021/acsnano.8b07595

3. 3.

   Ezawa M. Valley-polarized metals and quantum anomalous hall effect in silicene. Phys. Rev. Lett. 2012;109:055502.

   Not in our library10.1103/physrevlett.109.055502

4. 4.

   Jiang SW, Li LZ, Wang ZF, Mak KF, Shan J. Controlling magnetism in 2D CrI3 by electrostatic doping. Nat. Nanotechnol. 2018;13:549-553.

   Not in our library10.1038/s41565-018-0135-x

5. 5.

   Novoselov KS, et al. Electric field effect in atomically thin carbon films. Science. 2004;306:666-669.

   Not in our library10.1126/science.1102896

6. 6.

   Huang Y, et al. Reliable exfoliation of large-area high-quality flakes of graphene and other two-dimensional materials. ACS Nano. 2015;9:10612-10620.

   Not in our library10.1021/acsnano.5b04258

7. 7.

   Radisavljevic B, Radenovic A, Brivio J, Giacometti V, Kis A. Single-layer MoS2 transistors. Nat. Nanotechnol. 2011;6:147-150.

   Not in our library10.1038/nnano.2010.279

8. 8.

   McGuire MA, Dixit H, Cooper VR, Sales BC. Coupling of crystal structure and magnetism in the layered, ferromagnetic insulator CrI3. Chem. Mater. 2015;27:612-620.

   Not in our library10.1021/cm504242t

9. 9.

   Jiang, D. et al. High-Tc superconductivity in ultrathin Bi2Sr2CaCu2O8+x down to half-unit-cell thickness by protection with graphene. Nat. Commun.5, 5708 (2014).

   Not in our library10.1038/ncomms6708

10. 10.

    Tang SJ, et al. Quantum spin Hall state in monolayer 1T’-WTe2. Nat. Phys. 2017;13:683-687.

    Not in our library10.1038/nphys4174

11. 11.

    Zhang Y, et al. Superconducting gap anisotropy in monolayer FeSe thin film. Phys. Rev. Lett. 2016;117:117001.

    Not in our library10.1103/physrevlett.117.117001

12. 12.

    Novoselov KS, Mishchenko A, Carvalho A, Neto AHC. 2D materials and van der Waals heterostructures. Science. 2016;353:9439.

    Not in our library10.1126/science.aac9439

13. 13.

    Liu, Y. et al. Van der Waals heterostructures and devices. Nat. Rev. Mater.1, 16042 (2016).

    Not in our library

14. 14.

    Wang C, et al. Monolayer atomic crystal molecular superlattices. Nature. 2018;555:231-236.

    Not in our library10.1038/nature25774

15. 15.

    Li XS, Cai WW, Colombo L, Ruoff RS. Evolution of graphene growth on Ni and Cu by carbon isotope labeling. Nano Lett. 2009;9:4268-4272.

    Not in our library10.1021/nl902515k

16. 16.

    Moon IK, Lee J, Ruoff RS, Lee H. Reduced graphene oxide by chemical graphitization. Nat. Commun. 2010;1:73.

    Not in our library10.1038/ncomms1067

17. 17.

    Sutter PW, Flege JI, Sutter EA. Epitaxial graphene on ruthenium. Nat. Mater. 2008;7:406-411.

    Not in our library10.1038/nmat2166

18. 18.

    Meng L, et al. Buckled silicene formation on Ir(111). Nano Lett. 2013;13:685-690.

    Not in our library10.1021/nl304347w

19. 19.

    Liu H, Du YC, Deng YX, Ye PD. Semiconducting black phosphorus: synthesis, transport properties and electronic applications. Chem. Soc. Rev. 2015;44:2732-2743.

    Not in our library10.1039/c4cs00257a

20. 20.

    Coleman JN, et al. Two-dimensional nanosheets produced by liquid exfoliation of layered. Mater. Sci. 2011;331:568-571.

    Not in our library10.1126/science.1194975

21. 21.

    Fan XB, et al. Fast and efficient preparation of exfoliated 2H MoS2 nanosheets by sonication-assisted lithium intercalation and infrared laser-induced 1T to 2H phase reversion. Nano Lett. 2015;15:5956-5960.

    Not in our library10.1021/acs.nanolett.5b02091

22. 22.

    Desai SB, et al. Gold-mediated exfoliation of ultralarge optoelectronically-perfect monolayers. Adv. Mater. 2016;28:4053-4058.

    Not in our library10.1002/adma.201506171

23. 23.

    Velicky M, et al. Mechanism of gold-assisted exfoliation of centimeter-sized transition-metal dichalcogenide monolayers. ACS Nano. 2018;12:10463-10472.

    Not in our library10.1021/acsnano.8b06101

24. 24.

    Magda, G. Z. et al. Exfoliation of large-area transition metal chalcogenide single layers. Sci. Rep.5, 14714 (2015).

    Not in our library10.1038/srep14714

25. 25.

    Zhang YB, Tan YW, Stormer HL, Kim P. Experimental observation of the quantum Hall effect and Berry’s phase in graphene. Nature. 2005;438:201-204.

    Not in our library10.1038/nature04235

26. 26.

    Novoselov KS, et al. Two-dimensional gas of massless Dirac fermions in graphene. Nature. 2005;438:197-200.

    Not in our library10.1038/nature04233

27. 27.

    Cao Y, et al. Unconventional superconductivity in magic-angle graphene superlattices. Nature. 2018;556:43-50.

    Not in our library10.1038/nature26160

28. 28.

    Hao YF, et al. Oxygen-activated growth and bandgap tunability of large single-crystal bilayer graphene. Nat. Nanotechnol. 2016;11:426-431.

    Not in our library10.1038/nnano.2015.322

29. 29.

    Qiao JS, Kong XH, Hu ZX, Yang F, Ji W. High-mobility transport anisotropy and linear dichroism in few-layer black phosphorus. Nat. Commun. 2014;5:4475.

    Not in our library10.1038/ncomms5475

30. 30.

    Hu Z-X, Kong X, Qiao J, Normand B, Ji W. Interlayer electronic hybridization leads to exceptional thickness-dependent vibrational properties in few-layer black phosphorus. Nanoscale. 2016;8:2740-2750.

    Not in our library10.1039/c5nr06293d

31. 31.

    Qiao J, et al. Few-layer Tellurium: one-dimensional-like layered elementary semiconductor with striking physical properties. Sci. Bull. 2018;63:159-168.

    Not in our library10.1016/j.scib.2018.01.010

32. 32.

    Li W, et al. Experimental realization of honeycomb borophene. Sci. Bull. 2018;63:282-286.

    Not in our library10.1016/j.scib.2018.02.006

33. 33.

    Deng Y, et al. Gate-tunable room-temperature ferromagnetism in two-dimensional Fe3GeTe2. Nature. 2018;563:94-99.

    Not in our library10.1038/s41586-018-0626-9

34. 34.

    Giovannetti G, et al. Doping graphene with metal contacts. Phys. Rev. Lett. 2008;101:026803.

    Not in our library10.1103/physrevlett.101.026803

35. 35.

    Li H, et al. From bulk to monolayer MoS2: evolution of Raman scattering. Adv. Funct. Mater. 2012;22:1385-1390.

    Not in our library10.1002/adfm.201102111

36. 36.

    Mak KF, Lee C, Hone J, Shan J, Heinz TF. Atomically thin MoS2: a new Direct-gap semiconductor. Phys. Rev. Lett. 2010;105:136805.

    Not in our library10.1103/physrevlett.105.136805

37. 37.

    Du X, Skachko I, Barker A, Andrei EY. Approaching ballistic transport in suspended graphene. Nat. Nanotechnol. 2008;3:491-495.

    Not in our library10.1038/nnano.2008.199

38. 38.

    Lee C, Wei XD, Kysar JW, Hone J. Measurement of the elastic properties and intrinsic strength of monolayer graphene. Science. 2008;321:385-388.

    Not in our library10.1126/science.1157996

39. 39.

    Zhang Y, et al. Electronic structure, surface doping, and optical response in epitaxial WSe2 thin films. Nano Lett. 2016;16:2485-2491.

    Not in our library10.1021/acs.nanolett.6b00059

40. 40.

    Zhang HY, et al. Resolving deep quantum-well states in atomically thin 2H-MoTe2 flakes by nanospot angle-resolved photoemission spectroscopy. Nano Lett. 2018;18:4664-4668.

    Not in our library10.1021/acs.nanolett.8b00589

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