Metastable 1T′-phase transition metal dichalcogenides (1T′-TMDs) with semi-metallic natures have attracted increasing interest owing to their uniquely distorted structures and fascinating phase-dependent physicochemical properties. However, the synthesis of high-quality metastable 1T′-TMD crystals, especially for the group VIB TMDs, remains a challenge. Here, we report a general synthetic method for the large-scale preparation of metastable 1T′-phase group VIB TMDs, including WS2, WSe2, MoS2, MoSe2, WS2xSe2(1−x) and MoS2xSe2(1−x). We solve the crystal structures of 1T′-WS2, -WSe2, -MoS2 and -MoSe2 with single-crystal X-ray diffraction. The as-prepared 1T′-WS2 exhibits thickness-dependent intrinsic superconductivity, showing critical transition temperatures of 8.6 K for the thickness of 90.1 nm and 5.7 K for the single layer, which we attribute to the high intrinsic carrier concentration and the semi-metallic nature of 1T′-WS2. This synthesis method will allow a more systematic investigation of the intrinsic properties of metastable TMDs.
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The X-ray crystallographic coordinates for the structure reported in this study have been deposited at the Cambridge Crystallographic Data Centre under deposition numbers CSD 2062455, 2062456, 2062457 and 2062458. These data can be obtained free of charge from https://www.ccdc.cam.ac.uk/. Other data that support the findings of this study are available from the corresponding author upon reasonable request.
Cao, Y. et al. Correlated insulator behaviour at half-filling in magic-angle graphene superlattices. Nature 556, 80–84 (2018).
Cao, Y. et al. Unconventional superconductivity in magic-angle graphene superlattices. Nature 556, 43–50 (2018).
Yu, Y. et al. High phase-purity 1T′-MoS2- and 1T′-MoSe2-layered crystals. Nat. Chem. 10, 638–643 (2018).
Chaturvedi, A. et al. A universal method for rapid and large-scale growth of layered crystals. SmartMat 1, e1011 (2020).
Voiry, D., Mohite, A. & Chhowalla, M. Phase engineering of transition metal dichalcogenides. Chem. Soc. Rev. 44, 2702–2712 (2015).
Tan, C. et al. Recent advances in ultrathin two-dimensional nanomaterials. Chem. Rev. 117, 6225–6331 (2017).
Zhang, X., Lai, Z., Ma, Q. & Zhang, H. Novel structured transition metal dichalcogenide nanosheets. Chem. Soc. Rev. 47, 3301–3338 (2018).
Guo, C. et al. Observation of superconductivity in 1T′-MoS2 nanosheets. J. Mater. Chem. C 5, 10855–10860 (2017).
Lin, H. et al. Growth of environmentally stable transition metal selenide films. Nat. Mater. 18, 602–607 (2019).
Zhou, J. et al. Large-area and high-quality 2D transition metal telluride. Adv. Mater. 29, 1603471 (2017).
Sung, J. H. et al. Coplanar semiconductor–metal circuitry defined on few-layer MoTe2 via polymorphic heteroepitaxy. Nat. Nanotechnol. 12, 1064–1070 (2017).
Zhou, J. et al. A library of atomically thin metal chalcogenides. Nature 556, 355–359 (2018).
Zhang, H. Ultrathin two-dimensional nanomaterials. ACS Nano 9, 9451–9469 (2015).
Tan, C. et al. Preparation of high-percentage 1T-phase transition metal dichalcogenide nanodots for electrochemical hydrogen evolution. Adv. Mater. 30, 1705509 (2018).
Wypych, F. & Schollhorn, R. 1T-MoS2, a new metallic modification of molybdenum disulfide. J. Chem. Soc. Chem. Commun. 1386–1388 (1992).
Kappera, R. et al. Phase-engineered low-resistance contacts for ultrathin MoS2 transistors. Nat. Mater. 13, 1128–1134 (2014).
Voiry, D. et al. Enhanced catalytic activity in strained chemically exfoliated WS2 nanosheets for hydrogen evolution. Nat. Mater. 12, 850–855 (2013).
Zeng, Z. et al. Single-layer semiconducting nanosheets: high-yield preparation and device fabrication. Angew. Chem. Int. Ed. 50, 11093–11097 (2011).
Mahler, B., Hoepfner, V., Liao, K. & Ozin, G. A. Colloidal synthesis of 1T-WS2 and 2H-WS2 nanosheets: applications for photocatalytic hydrogen evolution. J. Am. Chem. Soc. 136, 14121–14127 (2014).
Sokolikova, M. S., Sherrell, P. C., Palczynski, P., Bemmer, V. L. & Mattevi, C. Direct solution-phase synthesis of 1T′ WSe2 nanosheets. Nat. Commun. 10, 712 (2019).
Geng, X. et al. Pure and stable metallic phase molybdenum disulfide nanosheets for hydrogen evolution reaction. Nat. Commun. 7, 10672 (2016).
Liu, L. et al. Phase-selective synthesis of 1T′ MoS2 monolayers and heterophase bilayers. Nat. Mater. 17, 1108–1114 (2018).
Lin, Y.-C., Dumcenco, D. O., Huang, Y.-S. & Suenaga, K. Atomic mechanism of the semiconducting-to-metallic phase transition in single-layered MoS2. Nat. Nanotechnol. 9, 391–396 (2014).
Duerloo, K.-A. N., Li, Y. & Reed, E. J. Structural phase transitions in two-dimensional Mo- and W-dichalcogenide monolayers. Nat. Commun. 5, 4214 (2014).
Kang, Y. et al. Plasmonic hot electron induced structural phase transition in a MoS2 monolayer. Adv. Mater. 26, 6467–6471 (2014).
Zink, N. et al. Selective synthesis of hollow and filled fullerene-like (IF) WS2 nanoparticles via metal–organic chemical vapor deposition. Chem. Mater. 19, 6391–6400 (2007).
Gong, Y. et al. Vertical and in-plane heterostructures from WS2/MoS2 monolayers. Nat. Mater. 13, 1135–1142 (2014).
Li, H. et al. From bulk to monolayer MoS2: evolution of raman scattering. Adv. Funct. Mater. 22, 1385–1390 (2012).
Timoshenko, J., Kuzmin, A. & Purans, J. EXAFS study of hydrogen intercalation into ReO3 using the evolutionary algorithm. J. Phys. Condens. Matter 26, 055401 (2014).
Ye, J. T. et al. Superconducting dome in a gate-tuned band insulator. Science 338, 1193–1196 (2012).
Fatemi, V. et al. Electrically tunable low-density superconductivity in a monolayer topological insulator. Science 362, 926–929 (2018).
Sajadi, E. et al. Gate-induced superconductivity in a monolayer topological insulator. Science 362, 922–925 (2018).
Chi, Z. et al. Superconductivity in pristine 2Ha-MoS2 at ultrahigh pressure. Phys. Rev. Lett. 120, 037002 (2018).
Saito, Y., Nojima, T. & Iwasa, Y. Highly crystalline 2D superconductors. Nat. Rev. Mater. 2, 16094 (2016).
Lu, J. et al. Full superconducting dome of strong Ising protection in gated monolayer WS2. Proc. Natl Acad. Sci. USA 115, 3551–3556 (2018).
Costanzo, D., Jo, S., Berger, H. & Morpurgo, A. F. Gate-induced superconductivity in atomically thin MoS2 crystals. Nat. Nanotechnol. 11, 339–344 (2016).
Lu, J. M. et al. Evidence for two-dimensional Ising superconductivity in gated MoS2. Science 350, 1353–1357 (2015).
Taniguchi, K., Matsumoto, A., Shimotani, H. & Takagi, H. Electric-field-induced superconductivity at 9.4 K in a layered transition metal disulphide MoS2. Appl. Phys. Lett. 101, 042603 (2012).
Jo, S., Costanzo, D., Berger, H. & Morpurgo, A. F. Electrostatically induced superconductivity at the surface of WS2. Nano Lett. 15, 1197–1202 (2015).
Shi, W. et al. Superconductivity series in transition metal dichalcogenides by ionic gating. Sci. Rep. 5, 12534 (2015).
Zeng, J. et al. Gate-induced interfacial superconductivity in 1T-SnSe2. Nano Lett. 18, 1410–1415 (2018).
Zhang, R. et al. Superconductivity in potassium-doped metallic polymorphs of MoS2. Nano Lett. 16, 629–636 (2016).
Qin, F. et al. Diameter-dependent superconductivity in individual WS2 nanotubes. Nano Lett. 18, 6789–6794 (2018).
Pan, X.-C. et al. Pressure-driven dome-shaped superconductivity and electronic structural evolution in tungsten ditelluride. Nat. Commun. 6, 7805 (2015).
Sharma, C. H., Surendran, A. P., Varma, S. S. & Thalakulam, M. 2D superconductivity and vortex dynamics in 1T-MoS2. Commun. Phys. 1, 90 (2018).
Cui, J. et al. Transport evidence of asymmetric spin-orbit coupling in few-layer superconducting 1Td-MoTe2. Nat. Commun. 10, 2044 (2019).
Beasley, M. R., Mooij, J. E. & Orlando, T. P. Possibility of vortex–antivortex pair dissociation in two-dimensional superconductors. Phys. Rev. Lett. 42, 1165–1168 (1979).
Skocpol, W. J. & Tinkham, M. Fluctuations near superconducting phase transitions. Rep. Prog. Phys. 38, 1049–1097 (1975).
Fan, Y. J. et al. Quantum superconductor–insulator transition in titanium monoxide thin films with a wide range of oxygen contents. Phys. Rev. B 98, 064501 (2018).
Jaeger, H. M., Haviland, D. B., Orr, B. G. & Goldman, A. M. Onset of superconductivity in ultrathin granular metal films. Phys. Rev. B 40, 182–196 (1989).
Yan, R. et al. Thickness dependence of superconductivity in ultrathin NbS2. Appl. Phys. Express 12, 023008 (2019).
Saito, Y., Kasahara, Y., Ye, J., Iwasa, Y. & Nojima, T. Metallic ground state in an ion-gated two-dimensional superconductor. Science 350, 409–413 (2015).
Hebard, A. F. & Paalanen, M. A. Magnetic-field-tuned superconductor–insulator transition in two-dimensional films. Phys. Rev. Lett. 65, 927–930 (1990).
Saito, Y., Nojima, T. & Iwasa, Y. Quantum phase transitions in highly crystalline two-dimensional superconductors. Nat. Commun. 9, 778 (2018).
Chen, Y. et al. Phase engineering of nanomaterials. Nat. Rev. Chem. 4, 243–256 (2020).
Li, H. et al. A universal, rapid method for clean transfer of nanostructures onto various substrates. ACS Nano 8, 6563–6570 (2014).
Du, Y. et al. XAFCA: a new XAFS beamline for catalysis research. J. Synchrotron Rad. 22, 839–843 (2015).
Ravel, B. & Newville, M. ATHENA, ARTEMIS, HEPHAESTUS: data analysis for X-ray absorption spectroscopy using IFEFFIT. J. Synchrotron Rad. 12, 537–541 (2005).
Blöchl, P. E. Projector augmented-wave method. Phys. Rev. B 50, 17953–17979 (1994).
Kresse, G. & Furthmüller, J. Efficient iterative schemes for ab initio total-energy calculations using a plane-wave basis set. Phys. Rev. B 54, 11169–11186 (1996).
Kresse, G. & Joubert, D. From ultrasoft pseudopotentials to the projector augmented-wave method. Phys. Rev. B 59, 1758–1775 (1999).
Perdew, J. P. & Wang, Y. Accurate and simple analytic representation of the electron-gas correlation energy. Phys. Rev. B 45, 13244–13249 (1992).
Perdew, J. P. et al. Atoms, molecules, solids, and surfaces: applications of the generalized gradient approximation for exchange and correlation. Phys. Rev. B 46, 6671–6687 (1992).
Porezag, D. & Pederson, M. R. Infrared intensities and Raman-scattering activities within density-functional theory. Phys. Rev. B 54, 7830–7836 (1996).
Perdew, J. P. & Wang, Y. Pair-distribution function and its coupling-constant average for the spin-polarized electron gas. Phys. Rev. B 46, 12947–12954 (1992).
Perdew, J. P., Burke, K. & Ernzerhof, M. Generalized gradient approximation made simple. Phys. Rev. Lett. 77, 3865–3868 (1996).
Baroni, S., de Gironcoli, S., Dal Corso, A. & Giannozzi, P. Phonons and related crystal properties from density-functional perturbation theory. Rev. Mod. Phys. 73, 515–562 (2001).
Paolo, G. et al. QUANTUM ESPRESSO: a modular and open-source software project for quantum simulations of materials. J. Phys. Condens. Matter 21, 395502 (2009).
Hamann, D. R., Schlüter, M. & Chiang, C. Norm-conserving pseudopotentials. Phys. Rev. Lett. 43, 1494–1497 (1979).
Allen, P. B. & Mitrović, B. in Solid State Physics Vol. 37 (eds Henry Ehrenreich et al.) Ch. 1 (Academic Press, 1983).
H.Z. acknowledges support from ITC via the Hong Kong Branch of National Precious Metals Material Engineering Research Center (NPMM), the Start-Up Grant (project no. 9380100) and grants (project nos. 9610478 and 1886921) from the City University of Hong Kong and the Science Technology and Innovation Committee of Shenzhen Municipality (grant no. JCYJ20200109143412311). Q.H. acknowledges the funding support from the Start-Up Grant (project no. 9610482) from the City University of Hong Kong. Y.S. and Y.M. acknowledge the funding support from the National Natural Science Foundation of China (under grant no. 11534003) and the Program for JLU Science and Technology Innovative Research Team and Science Challenge Project (no. TZ2016001). K.H. and D.V.M.R. acknowledge funding from the Accelerated Materials Development for Manufacturing Program at A*STAR via the AME Programmatic Fund by the Agency for Science, Technology and Research under grant no. A1898b0043. R.V.R. and V.S. acknowledge support by grants from the National Research Foundation, Prime Minister’s Office, Singapore, under its Campus for Research Excellence and Technological Enterprise (CREATE) programme. X.R.W. acknowledges supports from Academic Research Fund Tier 2 (grant no. MOE-T2EP50120-006) from Singapore Ministry of Education. We also thank W. Fernando for his generosity in providing us with his PhD thesis for our reference and S. Morris for the helpful discussions. We acknowledge the Facility for Analysis, Characterization, Testing and Simulation, Nanyang Technological University, Singapore, for use of their electron microscopy and X-ray facilities.
The authors declare no competing interests.
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Supplementary Figs. 1–64, Tables 1–7 and Notes 1–5.
The CIF document of the 1T′-WS2 crystal.
The CIF document of the 1T′-WSe2 crystal.
The CIF document of the 1T′-MoS2 crystal.
The CIF document of the 1T′-MoSe2 crystal.
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Lai, Z., He, Q., Tran, T.H. et al. Metastable 1T′-phase group VIB transition metal dichalcogenide crystals. Nat. Mater. 20, 1113–1120 (2021). https://doi.org/10.1038/s41563-021-00971-y
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