Highly Efficient Bulk-Crystal-Sized Exfoliation of 2D Materials under Ultrahigh Vacuum

0585020 - ÚFCH JH 2025 RIV US eng J - Journal Article
Haider, Golam - Gastaldo, Michele - Karim, Bazlul - Plšek, Jan - Varade, V. - Volochanskyi, Oleksandr - Vejpravová, J. - Kalbáč, Martin
Highly Efficient Bulk-Crystal-Sized Exfoliation of 2D Materials under Ultrahigh Vacuum.
ACS Applied Electronic Materials. (2024). E-ISSN 2637-6113
R&D Projects: GA ČR(CZ) GX20-08633X
Institutional support: RVO:61388955
Keywords : raman-scattering * shear * ultrahigh vacuum exfoliation * noble metals * large-area monolayers * interfacial interaction * Raman spectroscopy
OECD category: Physical chemistry
Impact factor: 4.7, year: 2022
Method of publishing: Open access
https://pubs.acs.org/doi/10.1021/acsaelm.3c01824?src=getftr

In the realm of materials science and nanotechnology, the pursuit of the scalable preparation of high-quality monolayers of two-dimensional (2D) materials is a significant challenge. Despite the widespread interest sparked by the unique quantum mechanical effects in these materials, achieving scalable and controlled syntheses remains hindered by a lack of suitable techniques. This work presents a facile exfoliation approach that successfully yields bulk-crystal-sized 2D monolayers, approaching 100% under ultrahigh vacuum (UHV) conditions. The process was demonstrated by exfoliating MoS2 on Au and Ag substrates. Raman spectroscopy reveals a strong dispersive interaction at the metal/MoS2 interface, inducing a high strain field on the topmost layer of the bulk crystal. This strain field's inhomogeneous distribution reduces interlayer van der Waals interactions, enhancing the selectivity of monolayer exfoliation. Beyond scalable exfoliation, our method opens avenues for obtaining monolayers of materials unstable under ambient conditions, emphasizing its broader applicability in advancing the synthesis of 2D materials for diverse applications.
Permanent Link: https://hdl.handle.net/11104/0352789