Unveiling the origin of n-type doping of natural MoS2: carbon
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Abstract
Abstract MoS 2 has attracted intense interest in many applications. Natural MoS 2 and field-effect transistors made of it generally exhibit n -type characteristics, but its origin is unknown. Herein, we show that C is the origin of the universal n -type doping of natural MoS 2 . Photoemission spectroscopies reveal that while many MoS 2 samples with C detected are n -type, some without C exhibit p -type characteristics. The C-free, p -type MoS 2 changes to n -type over time with the concurrent appearance of C that is out-diffused from bulk, indicating that C induces the n -type doping. The C-origin is verified by C-deposition and supported by theoretical calculations. This carbon appears as nanometer-scale defects frequently observed in scanning tunneling microscopy. In addition, we propose, based on the calculations, that S vacancies are responsible for the p -type characteristics, which contrasts with the widespread belief. This work provides new perspectives on MoS 2 doping and presents a new direction for fabricating reliable MoS 2 devices.
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Research context
OpenAlex topics: 2D Materials and Applications · MXene and MAX Phase Materials · Graphene research and applications
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References (52)
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1. Wang, Q. H., Kalantar-Zadeh, K., Kis, A., Coleman, J. N. & Strano, M. S. Electronics and optoelectronics of two-dimensional transition metal dichalcogenides. Nat. Nanotechnol. 7, 699–712 (2012).10.1038/nnano.2012.193 ↗
2. Schmidt, H., Giustiniano, F. & Eda, G. Electronic transport properties of transition metal dichalcogenide field-effect devices: surface and interface effects. Chem. Soc. Rev. 44, 7715–7736 (2015).10.1039/C5CS00275C ↗
3. Manzeli, S., Ovchinnikov, D., Pasquier, D., Yazyev, O. V. & Kis, A. 2D transition metal dichalcogenides. Nat. Rev. Mater. 2, 17033 (2017).10.1038/natrevmats.2017.33 ↗
4. Radisavljevic, B., Radenovic, A., Brivio, J., Giacometti, V. & Kis, A. Single-layer MoS2 transistors. Nat. Nanotechnol. 6, 147–150 (2011).10.1038/nnano.2010.279 ↗
5. Kim, S. et al. High-mobility and low-power thin-film transistors based on multilayer MoS2 crystals. Nat. Commun. 3, 1011 (2012).
6. Schmidt, H. et al. Transport properties of monolayer MoS2 grown by chemical vapor deposition. Nano Lett. 14, 1909–1913 (2014).10.1021/nl4046922 ↗
7. Yin, Z. et al. Single-layer MoS2 phototransistors. ACS Nano 6, 74–80 (2012).10.1021/nn2024557 ↗
8. Mak, K. F. et al. Tightly bound trions in monolayer MoS2. Nat. Mater. 12, 207–211 (2013).10.1038/nmat3505 ↗
9. Bernardi, M., Palummo, M. & Grossman, J. C. Extraordinary sunlight absorption and one nanometer thick photovoltaics using two-dimensional monolayer materials. Nano Lett. 13, 36643670 (2013).10.1021/nl401544y ↗
10. Wi, S. et al. Enhancement of photovoltaic response in multilayer MoS2 induced by plasma doping. ACS Nano 8, 5270–5281 (2014).10.1021/nn5013429 ↗
11. Zong, X. et al. Photocatalytic H2 evolution on MoS2/CdS catalysts under visible light irradiation. J. Phys. Chem. C 114, 1963–1968 (2010).10.1021/jp904350e ↗
12. Lukowski, M. A. et al. Enhanced hydrogen evolution catalysis from chemically exfoliated metallic MoS2 nanosheets. J. Am. Chem. Soc. 135, 10274–10277 (2013).10.1021/ja404523s ↗
13. Li, H. et al. Fabrication of single- and multilayer MoS2 film-based FET for sensing NO at RT. Small 8, 63–67 (2012).10.1002/smll.201101016 ↗
14. Bhimanapati, G. R. et al. Recent advances in two-dimensional materials beyond graphene. ACS Nano 9, 11509–11539 (2015).10.1021/acsnano.5b05556 ↗
15. Wang, F. et al. Progress on electronic and optoelectronic devices of 2D layered semiconducting materials. Small 13, 1604298 (2017).10.1002/smll.201604298 ↗
16. Li, S. et al. p-/n-Type modulation of 2D transition metal dichalcogenides for electronic and optoelectronic devices. Nano Res. 15, 123–144 (2022).10.1007/s12274-021-3500-2 ↗
17. Lee, G. H. et al. Highly stable, dual-gated MoS2 transistors encapsulated by hexagonal boron nitride with gate-controllable contact, resistance, and threshold voltage. ACS Nano 9, 7019–7026 (2015).10.1021/acsnano.5b01341 ↗
18. Zou, X. et al. Dielectric engineering of a boron nitride/hafnium oxide heterostructure for high-performance 2D field effect transistors. Adv. Mater. 28, 2062–2069 (2016).10.1002/adma.201505205 ↗
19. Liu, Y. et al. Approaching the Schottky-Mott limit in van der Waals metal-semiconductor junctions. Nature 557, 696–700 (2018).10.1038/s41586-018-0129-8 ↗
20. Lee, Y. H. et al. Synthesis of large-area MoS2 atomic layers with chemical vapor deposition. Adv. Mater. 24, 2320–2325 (2012).10.1002/adma.201104798 ↗
21. Liu, K. K. et al. Growth of large-area and highly crystalline MoS2 thin layers on insulating substrates. Nano Lett. 12, 1538–1544 (2012).10.1021/nl2043612 ↗
22. Baugher, B. W. H., Churchill, H. O. H., Yang, Y. & Jarillo-Herrero, P. Intrinsic electronic transport properties of high-quality monolayer and bilayer MoS2. Nano Lett. 13, 4212–4216 (2013).10.1021/nl401916s ↗
23. Ahn, J. H., Parkin, W. M., Naylor, C. H., Johnson, A. T. C. & Drndić, M. Ambient effects on electrical characteristics of CVD-grown monolayer MoS2 field-effect transistors. Sci. Rep. 7, 4075 (2017).
24. Zhang, Y., Ye, J., Matsuhashi, Y. & Iwasa, Y. Ambipolar MoS2 thin flake transistors. Nano Lett. 12, 1136–1140 (2012).10.1021/nl2021575 ↗
25. Bao, W., Cai, X., Kim, D., Sridhara, K. & Fuhrer, M. S. High mobility ambipolar MoS2 field-effect transistors: substrate and dielectric effects. Appl. Phys. Lett. 102, 042104 (2013).10.1063/1.4789365 ↗
26. Han, S. W. et al. Band-gap expansion in the surface-localized electronic structure of MoS2(0002). Phys. Rev. B 86, 115105 (2012).10.1103/PhysRevB.86.115105 ↗
27. Jin, W. et al. Osgood, Direct measurement of the thickness-dependent electronic band structure of MoS2 using angle-resolved photoemission spectroscopy. Phys. Rev. Lett. 111, 106801 (2013).10.1103/PhysRevLett.111.106801 ↗
28. Alidoust, N. et al. Observation of monolayer valence band spin-orbit effect and induced quantum well states in MoX2. Nat. Commun. 5, 4673 (2014).10.1038/ncomms5673 ↗
29. Miwa, J. A. et al. Electronic structure of epitaxial single-layer MoS2. Phys. Rev. Lett. 114, 046802 (2015).10.1103/PhysRevLett.114.046802 ↗
30. Latzke, D. K. et al. Electronic structure, spin-orbit coupling, and interlayer interaction in bulk MoS2 and WS2. Phys. Rev. B 91, 235202 (2015).10.1103/PhysRevB.91.235202 ↗
31. Qiu, H. et al. Hopping transport through defect-induced localized states in molybdenum disulphide. Nat. Commun. 4, 2642 (2013).10.1038/ncomms3642 ↗
32. McDonnell, S., Addou, R., Buie, C., Wallace, R. M. & Hinkle, C. L. Defect-dominated doping and contact resistance in MoS2. ACS Nano 8, 2880–2888 (2014).10.1021/nn500044q ↗
33. Lu, C. P., Li, G., Mao, J., Wang, L. M. & Andrei, E. Y. Bandgap, mid-gap states, and gating effects in MoS2. Nano Lett. 14, 4628–4633 (2014).10.1021/nl501659n ↗
34. Park, J. H. et al. Defect passivation of transition metal dichalcogenides via a charge transfer van der Waals interface. Sci. Adv. 3, e1701661 (2017).10.1126/sciadv.1701661 ↗
35. Noh, J. Y., Kim, H. & Kim, Y. S. Stability and electronic structures of native defects in single-layer MoS2. Phys. Rev. B 89, 205417 (2014).10.1103/PhysRevB.89.205417 ↗
36. Komsa, H. P. & Krasheninnikov, A. V. Native defects in bulk and monolayer MoS2 from first principles. Phys. Rev. B 91, 125304 (2015).10.1103/PhysRevB.91.125304 ↗
37. Pandey, M. et al. Defect-tolerant monolayer transition metal dichalcogenides. Nano Lett. 16, 2234–2239 (2016).10.1021/acs.nanolett.5b04513 ↗
38. Singh, A. & Singh, A. K. Origin of n-type conductivity of monolayer MoS2. Phys. Rev. B 99, 121201 (2019). (R).10.1103/PhysRevB.99.121201 ↗
39. Addou, R., Colombo, L. & Wallace, R. M. Surface defects on natural MoS2. ACS Appl. Mater. Interfaces 7, 11921–11929 (2015).10.1021/acsami.5b01778 ↗
40. Bampoulis, P. et al. Defect dominated charge transport and Fermi level pinning in MoS2/metal contacts. ACS Appl. Mater. Interfaces 9, 19278–19286 (2017).10.1021/acsami.7b02739 ↗
41. Liu, X., Balla, I., Bergeron, H. & Hersam, M. C. Point defects and grain boundaries in rotationally commensurate MoS2 on epitaxial graphene. J. Phys. Chem. C 120, 20798–20805 (2016).10.1021/acs.jpcc.6b02073 ↗
42. Böker, T. et al. Band structure of MoS2, MoSe2, and a-MoTe2: angle-resolved photoelectron spectroscopy and ab initio calculations. Phys. Rev. B 64, 235305 (2001).10.1103/PhysRevB.64.235305 ↗
43. Vancsó, P. et al. The intrinsic defect structure of exfoliated MoS2 single layers revealed by scanning tunneling microscopy. Sci. Rep. 6, 29726 (2016).10.1038/srep29726 ↗
44. Donarelli, M., Bisti, F., Perrozzi, F. & Ottaviano, L. Tunable sulfur desorption in exfoliated MoS2 by means of thermal annealing in ultra-high vacuum. Chem. Phys. Lett. 588, 198–202 (2013).10.1016/j.cplett.2013.10.034 ↗
45. Zhang, X. et al. Unravelling the effect of sulfur vacancies on the electronic structure of the MoS2 crystal. Phys. Chem. Chem. Phys. 22, 21776–21783 (2020).10.1039/C9CP07004D ↗
46. Chen, Y. et al. Tuning electronic structure of single layer MoS2 through defect and interface engineering. ACS Nano 12, 2569 (2018).10.1021/acsnano.7b08418 ↗
47. Bussolotti, F., Yang, J., Kawai, H., Wong, C. P. Y. & Goh, K. E. J. Impact of S‑vacancies on the charge injection barrier at the electrical contact with the MoS2 monolayer. ACS Nano 15, 2686–2579 (2021).10.1021/acsnano.0c07982 ↗
48. Siao, M. D. et al. Two-dimensional electronic transport and surface electron accumulation in MoS2. Nat. Commun. 9, 1442 (2018).10.1038/s41467-018-03824-6 ↗
49. McGovern, I. T., Williams, R. H. & Mee, C. H. B. Electronic properties of cleaved molybdenum disulphide surfaces. Surf. Sci. 46, 427–440 (1974).10.1016/0039-6028(74)90318-5 ↗
50. Zhang, F. et al. Carbon doping of WS2 monolayers: bandgap reduction and p-type doping transport. Sci. Adv. 5, eaav5003 (2019).10.1126/sciadv.aav5003 ↗
51. Cochrane, K. et al. Intentional carbon doping reveals CH as an abundant charged impurity in nominally undoped synthetic WS2 and WSe2. 2D Mater. 7, 031003 (2020).10.1088/2053-1583/ab8543 ↗
52. Kresse, G. & Furthmuller, J. Efficient iterative schemes for ab initio total-energy calculations using a plane-wave basis set. Phys. Rev. B 54, 11169 (1996).10.1103/PhysRevB.54.11169 ↗