Solution-processable 2D semiconductor inks based on electrochemical molecular intercalation and exfoliation of bulk layered crystals using organic cations has offered an alternative pathway to low-cost fabrication of large-area flexible and wearable electronic devices. However, the growth of large-piece bulk crystals as starting material relies on costly and prolonged high-temperature process, representing a critical roadblock towards practical and large-scale applications. Here we report a general liquid-metal-assisted approach that enables the electrochemical molecular intercalation of low-cost and readily available crystal powders. The resulted solution-processable MoS2 nanosheets are of comparable quality to those exfoliated from bulk crystals. Furthermore, this method can create a rich library of functional 2D electronic inks ( >50 types), including 2D wide-bandgap semiconductors of low electrical conductivity. Lastly, we demonstrated the all-solution-processable integration of 2D semiconductors with 2D conductors and 2D dielectrics for the fabrication of large-area thin-film transistors and memristors at a greatly reduced cost.

Department of Chemistry Engineering Research Center of Advanced Rare Earth Materials Tsinghua University Beijing 100084 China

Department of Inorganic Chemistry University of Chemistry and Technology Prague Technická 5 166 28 Prague 6 Czech Republic

Nat Commun. 2024 Oct 23;15(1):9137. doi: 10.1038/s41467-024-53248-8. PubMed

See more in PubMed

Nicolosi, V., Chhowalla, M., Kanatzidis, M. G., Strano, M. S. & Coleman, J. N. Liquid exfoliation of layered materials. Science340, 1226419 (2013).

Lin, Z. et al. Solution-processable 2D semiconductors for high-performance large-area electronics. Nature562, 254–258 (2018). PubMed

Yang, R. et al. High-yield production of mono- or few-layer transition metal dichalcogenide nanosheets by an electrochemical lithium ion intercalation-based exfoliation method. Nat. Protoc.17, 358–377 (2022). PubMed

Yan, Z. et al. Highly stretchable van der Waals thin films for adaptable and breathable electronic membranes. Science375, 852–859 (2022). PubMed

Tang, B. et al. Wafer-scale solution-processed 2D material analog resistive memory array for memory-based computing. Nat. Commun.13, 3037 (2022). PubMed PMC

Lin, Z., Huang, Y. & Duan, X. Van der Waals thin-film electronics. Nat. Electron.2, 378–388 (2019).

Kelly, A. G. et al. All-printed thin-film transistors from networks of liquid-exfoliated nanosheets. Science356, 69–73 (2017). PubMed

Pinilla, S., Coelho, J., Li, K., Liu, J. & Nicolosi, V. Two-dimensional material inks. Nat. Rev. Mater.7, 717–735 (2022).

McManus, D. et al. Water-based and biocompatible 2D crystal inks for all-inkjet-printed heterostructures. Nat. Nanotechnol.12, 343–350 (2017). PubMed

Li, L. et al. Interface capture effect printing atomic-thick 2D semiconductor thin films. Adv. Mater.34, 2207392 (2022). PubMed

Carey, T. et al. Fully inkjet-printed two-dimensional material field-effect heterojunctions for wearable and textile electronics. Nat. Commun.8, 1202 (2017). PubMed PMC

Kim, J. et al. All-solution-processed van der Waals heterostructures for wafer-scale electronics. Adv. Mater.34, 2106110 (2022). PubMed

Zou, T. & Noh, Y. Y. Solution-processed 2D transition metal dichalcogenides: materials to CMOS electronics. Acc. Mater. Res.4, 548–559 (2023).

Liu, K. et al. Growth of large-area and highly crystalline MoS2 thin layers on insulating substrates. Nano Lett.12, 1538–1544 (2012). PubMed

Li, W. et al. Large-scale ultra-robust MoS2 patterns directly synthesized on polymer substrate for flexible sensing electronics. Adv. Mater.35, 2207447 (2023). PubMed

Ippolito, S. et al. Covalently interconnected transition metal dichalcogenide networks via defect engineering for high-performance electronic devices. Nat. Nanotechnol.16, 592–598 (2021). PubMed

Zhang, C. et al. Mass production of 2D materials by intermediate-assisted grinding exfoliation. Natl Sci. Rev.7, 324–332 (2020). PubMed PMC

Kuo, L. et al. All-printed ultrahigh-responsivity MoS2 nanosheet photodetectors enabled by megasonic exfoliation. Adv. Mater.34, 2203772 (2022). PubMed

Zeng, Z. et al. Single-layer semiconducting nanosheets: high-yield preparation and device fabrication. Angew. Chem. Int. Ed.50, 11093–11097 (2011). PubMed

Ambrosi, A., Sofer, Z. & Pumera, M. Electrochemical exfoliation of layered black phosphorus into phosphorene. Angew. Chem. Int. Ed.56, 10443–10445 (2017). PubMed

Ambrosi, A. & Pumera, M. Exfoliation of layered materials using electrochemistry. Chem. Soc. Rev.47, 7213–7224 (2018). PubMed

Peng, J. et al. Very large-sized transition metal dichalcogenides monolayers from fast exfoliation by manual shaking. J. Am. Chem. Soc.139, 9019–9025 (2017). PubMed

Zheng, J. et al. High yield exfoliation of two-dimensional chalcogenides using sodium naphthalenide. Nat. Commun.5, 2995 (2014). PubMed

Shi, Z. et al. Phase-dependent growth of Pt on MoS2 for highly efficient H2 evolution. Nature621, 300–305 (2023). PubMed

Wang, S. et al. Electrochemical molecular intercalation and exfoliation of solution-processable two-dimensional crystals. Nat. Protoc.18, 2814–2837 (2023). PubMed

Shi, H. et al. Ultrafast electrochemical synthesis of defect-free In2Se3 flakes for large-area optoelectronics. Adv. Mater.32, 1907244 (2020). PubMed

Yang, S. et al. A delamination strategy for thinly layered defect-free high-mobility black phosphorus flakes. Angew. Chem. Int. Ed.57, 4677–4681 (2018). PubMed

Li, J. et al. Printable two-dimensional superconducting monolayers. Nat. Mater.20, 181–187 (2021). PubMed

Peng, J. et al. Stoichiometric two-dimensional non-van der Waals AgCrS2 with superionic behaviour at room temperature. Nat. Chem.13, 1235–1240 (2021). PubMed

Yu, W. et al. High-yield exfoliation of monolayer 1T′-MoTe2 as saturable absorber for ultrafast photonics. ACS Nano15, 18448–18457 (2021). PubMed

Zou, T. et al. High-performance solution-processed 2D p-type WSe2 transistors and circuits through molecular doping. Adv. Mater.35, 2208934 (2023). PubMed

Kwon, Y. A. et al. Wafer-scale transistor arrays fabricated using slot-die printing of molybdenum disulfide and sodium-embedded alumina. Nat. Electron.6, 443–450 (2023).

Hao, Q. et al. Surface-modified ultrathin InSe nanosheets with enhanced stability and photoluminescence for high-performance optoelectronics. ACS Nano14, 11373–11382 (2020). PubMed

Wells, R. A. et al. High performance semiconducting nanosheets via a scalable powder-based electrochemical exfoliation technique. ACS Nano16, 5719–5730 (2022). PubMed

Zavabeti, A. et al. A liquid metal reaction environment for the room-temperature synthesis of atomically thin metal oxides. Science358, 332–335 (2017). PubMed

Zavabeti, A. et al. High-mobility p-type semiconducting two-dimensional β-TeO2. Nat. Electron.4, 277–283 (2021).

Kong, W. et al. Oxide-mediated formation of chemically stable tungsten-liquid metal mixtures for enhanced thermal interfaces. Adv. Mater.31, 1904309 (2019). PubMed

Wang, C. et al. A general approach to composites containing nonmetallic fillers and liquid gallium. Sci. Adv.7, eabe3767 10.1126/sciadv.abe3767 (2021). PubMed PMC

Khan, M. R., Eaker, C. B., Bowden, E. F. & Dickey, M. D. Giant and switchable surface activity of liquid metal via surface oxidation. Proc. Natl. Acad. Sci. USA111, 14047–14051 (2014). PubMed PMC

Eaker, C. B., Hight, D. C., O’Regan, J. D., Dickey, M. D. & Daniels, K. E. Oxidation-mediated fingering in liquid metals. Phys. Rev. Lett.119, 174502 (2017). PubMed

Mayyas, M. et al. Liquid-metal-templated synthesis of 2D graphitic materials at room temperature. Adv. Mater.32, 2001997 (2020). PubMed

Mayyas, M. et al. Gallium-based liquid metal reaction media for interfacial precipitation of bismuth nanomaterials with controlled phases and morphologies. Adv. Funct. Mater.32, 2108673 (2022).

Lin, Z. et al. High-yield exfoliation of 2D semiconductor monolayers and reassembly of organic/inorganic artificial superlattices. Chem7, 1887–1902 (2021).

Xue, J. et al. Solution-processable assembly of 2D semiconductor thin films and superlattices with photoluminescent monolayer inks. Chem10, 1471–1484 (2024).

Joung, S. Y. et al. All-solution-processed high-performance MoS2 thin-film transistors with a quasi-2D perovskite oxide dielectric. ACS Nano18, 1958–1968 (2024). PubMed

Osada, M. et al. Robust high-κ response in molecularly thin perovskite nanosheets. ACS Nano4, 5225–5232 (2010). PubMed