Seed-mediated self-driven nucleation growth of doped monolayer WS₂ film

Abstract

The substitutional doping of two-dimensional (2D) transition metal dichalcogenides (TMDs) is essential for tuning their electronic and optoelectronic properties. However, conventional doping methods often suffer from the edge enrichment by dopant atoms, particularly for rare-earth dopants with large ionic radii, owing to their tendency to migrate toward high-energy edge sites during growth. Herein, we present a seed-mediated, self-driven nucleation strategy that leverages the high surface energy of stepped sapphire substrates to pre-adsorb dopant atoms at the step edges. These sites guide the localized nucleation and incorporation of the dopants, thereby effectively suppressing edge segregation. Using this approach, we synthesized centimeter-scale monolayer Yb-doped WS₂ films with incorporated substitutional atoms, along with other metal-doped WS₂ films. The introduction of mid-gap states near the conduction band in monolayer Yb-doped WS₂ films was further demonstrated by the characterization of the bound exciton emission and electronic density of states. This study broadens the pathways for the controllable synthesis of substitutional 2D materials and extends the potential for developing novel 2D optoelectronic devices.

Keywords

doping growth / large-area thin film / rare earth elements / step substrate / tungsten disulfide

References

[1] Li T, Guo W, Ma L, et al. Epitaxial growth of wafer-scale molybdenum disulfide semiconductor single crystals on sapphire. Nat Nanotechnol. 2021; 16(11): 1201-1207.

[2] Liu Y, Duan X, Shin HJ, Park S, Huang Y, Duan X. Promises and prospects of two-dimensional transistors. Nature. 2021; 591(7848): 43-53.

[3] Ma L, Wang X, Wang H, et al. Van Der Waals self-epitaxial growth of inch-sized superconducting niobium Diselenide films. Nano Lett. 2023; 23(15): 6892-6899.

[4] Ma L, Zhu J, Li W, et al. Immobilized precursor particle driven growth of centimeter-sized MoTe₂ Monolayer. J Am Chem Soc. 2021; 143(33): 13314-13324.

[5] Zhu J, Li W, Huang R, et al. One-pot selective epitaxial growth of large WS₂/MoS₂ Lateral and vertical heterostructures. J Am Chem Soc. 2020; 142(38): 16276-16284.

[6] Bai G, Yuan S, Zhao Y, et al. 2D layered materials of rare-earth Er-oped MoS₂ with NIR-to-NIR Down- and up-conversion photoluminescence. Adv Mater. 2016; 28(34): 7472-7477.

[7] Das M, Sen D, Sakib NU, et al. High-performance p-type field-effect transistors using substitutional doping and thickness control of two-dimensional materials. Nat Electron. 2024; 8: 24.

[8] Shen PC, Su C, Lin Y, et al. Ultralow contact resistance between semimetal and monolayer semiconductors. Nature. 2021; 593(7858): 211-217.

[9] Wang C, Xu L, Jin H, et al. Yb/Er coordinatively doping in bilayer WSe₂ for fascinating up-conversion luminescence. Nano Energy. 2020; 78:105317.

[10] Loh L, Ho YW, Xuan F, et al. Nb impurity-bound excitons as quantum emitters in monolayer WS₂. Nat Commun. 2024; 15(1): 10035.

[11] Li H, Cheng M, Wang P, et al. Reducing contact resistance and boosting device performance of monolayer MoS2 by in situ fe doping. Adv Mater. 2022; 34:e2200885.

[12] Ren C, Peng J, Chen H, et al. Understanding dopant–host interactions on electronic structures and optical properties in Ce-doped WS₂ Monolayers. Adv Funct Mater. 2023; 33(32):2301533.

[13] Xu D, Chen W, Zeng M, et al. Crystal-field tuning of photoluminescence in two-dimensional materials with embedded lanthanide ions. Angew Chem Int Ed. 2018; 57(3): 755-759.

[14] Bai G, Yang Z, Lin H, Jie W, Hao J. Lanthanide Yb/Er co-doped semiconductor layered WSe₂ nanosheets with near-infrared luminescence at telecommunication wavelengths. Nanoscale. 2018; 10(19): 9261-9267.

[15] Fu W, John M, Maddumapatabandi TD, et al. Toward edge engineering of two-dimensional layered transition-metal dichalcogenides by chemical vapor deposition. ACS Nano. 2023; 17(17): 16348-16368.

[16] An GH, Yun SJ, Lee YH, Lee HS. Growth Mechanism of Alternating Defect Domains in Hexagonal WS2 via Inhomogeneous W-Precursor Accumulation. Small. 2020; 16:2003326.

[17] Yang W, Zhang S, Chen Q, et al. Conversion of intercalated MoO₃ to multi-heteroatoms-doped MoS₂ with high hydrogen evolution activity. Adv Mater. 2020; 32(30):2001167.

[18] Ouyang Y, Li W, Zhang C, et al. Hydroxide modified synthesis of atomically-doped photoluminescent WS₂ monolayers. Adv Opt Mater. 2024; 12(12):2302596.

[19] Ra HS, Jeong MH, Yoon T, Kim S, Song YJ, Lee JS. Probing the Importance of Charge Balance and Noise Current in WSe2/WS2/MoS2 van der Waals Heterojunction Phototransistors by Selective Electrostatic Doping. Adv Sci. 2020; 7:2001475.

[20] Fu JH, Min J, Chang CK, et al. Oriented lateral growth of two-dimensional materials on c-plane sapphire. Nat Nanotechnol. 2023; 18(11): 1289-1294.

[21] Wang J, Xu X, Cheng T, et al. Dual-coupling-guided epitaxial growth of wafer-scale single-crystal WS₂ monolayer on vicinal a-plane sapphire. Nat Nanotechnol. 2022; 17(1): 33-38.

[22] Zhu H, Nayir N, Choudhury TH, et al. Step engineering for nucleation and domain orientation control in WSe₂ epitaxy on c-plane sapphire. Nat Nanotechnol. 2023; 18(11): 1295-1302.

[23] Norris DJ, Efros AL, Erwin SC. Doped nanocrystals. Science. 2008; 319(5871): 1776-1779.

[24] Watzky MA, Finney EE, Finke RG. Transition-metal nanocluster size vs formation time and the catalytically effective nucleus number: a mechanism-based treatment. J Am Chem Soc. 2008; 130(36): 11959-11969.

[25] Wang X, Ma L, Wang C, et al. Seed engineering toward layer-regulated growth of magnetic semiconductor VS₂. Adv Funct Mater. 2023; 33(19):2213295.

[26] Kim H, Mattevi C, Calvo MR, et al. Activation energy paths for graphene nucleation and growth on Cu. ACS Nano. 2012; 6(4): 3614-3623.

[27] Tersoff J, Denier van der Gon AW, Tromp RM. Critical Island size for layer-by-layer growth. Phys Rev Lett. 1994; 72(2): 266-269.

[28] Xu X, Zhang Z, Qiu L, et al. Ultrafast growth of single-crystal graphene assisted by a continuous oxygen supply. Nat Nanotechnol. 2016; 11(11): 930-935.

[29] Cui J, Hope GA. Raman and fluorescence spectroscopy of CeO2, Er2O3, Nd2O3, Tm2O3, Yb2O3, La2O3, and Tb4O7. J Spectrosc. 2015; 2015:8.

[30] Lee SH, Cheong HM, Tracy E, Mascarenhas A, Benson DK, Deb SK. Raman spectroscopic studies of electrochromic a-WO3. Electrochim Acta. 1998; 44(18): 3111.

[31] Mouri S, Miyauchi Y, Matsuda K. Tunable photoluminescence of monolayer MoS₂ via chemical doping. Nano Lett. 2013; 13(12): 5944-5948.

[32] Loh LY, Zhang ZP, Bosaman M, Eda G. Substitutional doping in 2D transition metal dichalcogenides. Nano Res. 2021; 16(6): 1668.

[33] Schuler B, Lee JH, Kastl C, et al. How substitutional point defects in two-dimensional WS₂ induce charge localization, spin–orbit splitting, and strain. ACS Nano. 2019; 13(9): 10520-10534.

[34] Barja S, Refaely-Abramson S, Schuler B, et al. Identifying substitutional oxygen as a prolific point defect in monolayer transition metal dichalcogenides. Nat Commun. 2019; 10(1): 3382.

[35] Tumino F, Casari CS, Li Bassi A, Tosoni S. Nature of point defects in single-layer MoS₂ supported on Au(111). J Phys Chem C. 2020; 124(23): 12424-12431.

[36] Huang X, Liu C, Zhou P. 2D semiconductors for specific electronic applications: from device to system. NPJ 2D Mater Appl. 2022; 6: 51.

[37] Krane N, Lotze C, Franke KJ. Moiré structure of MoS₂ on Au(111): local structural and electronic properties. Surf Sci. 2018; 678: 136-142.

[38] Zhang K, Bersch BM, Joshi J, et al. Tuning the electronic and photonic properties of monolayer MoS₂ via in situ rhenium substitutional doping. Adv Funct Mater. 2018; 28(16):1706950.

[39] Greben K, Arora S, Harats MG, Bolotin KI. Intrinsic and extrinsic defect-related excitons in TMDCs. Nano Lett. 2020; 20(4): 2544-2550.

[40] Ross JS, Wu S, Yu H, et al. Electrical control of neutral and charged excitons in a monolayer semiconductor. Nat Commun. 2013; 4(1): 1474.

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