Interlayer Mobility Control of 2D-Layered Crystals for Delamination of Nanosheets

J. Am. Chem. Soc. 2026, doi.org/10.1021/jacs.6c07562.

To maintain consistent properties of delaminated two-dimensional nanosheets, mild methods to preserve large lateral sizes and crystallinity during the delamination of bulk crystals are desired. This study introduces a gentle, solution-based on-substrate delamination strategy that avoids forming colloidal free-standing nanosheets by postponing the delamination process until the materials are deposited on the substrate, thereby preventing physical fragmentation in solution. By comparing cone-type and cylinder-type molecular intercalates (oleylamine and hexadecylamine), we identify interlayer mobility as a governing parameter for delamination in intercalation-accessible layered crystals, eliminating the need for external energy input such as sonication. Operando microscopic analyses reveal the importance of the gas–liquid interface during the evaporation process of drop-cast samples, which induces shear forces necessary for delamination. Application to a range of layered oxides and chalcogenides (HNb₃O₈, HTaMoO₆, HTiNbO₅, MoO₃, V₂O₅, and TiS₂) illustrates the transferability of this working principle across chemically distinct layered materials sharing sufficient interlayer adaptability. These proof-of-concept findings demonstrate that controlling interlayer mobility through molecular engineering provides an alternative route to producing large-area, high-quality 2D nanosheets.