Universal Principle for Large-Scale Production of a High-Quality Two-Dimensional Monolayer via Positive Charge-Driven Exfoliation

On the basis of the intrinsic characteristics of the layered materials, here we report a universal principle for the production of intact monolayers via layer by-layer exfoliation from their bulk via positive charge doping. At experimental accessible densities (n(c)) of similar to 1014 cm(-2), various multilayer crystals, including graphite, hexagonal boron nitride, transition metal dichalcogenides, MXenes, and black phosphorus, can be exfoliated into the corresponding monolayers through ab initio density functional theory stimulations. The carrier critical thresholds for exfoliating are found to be nearly independent of thickness but dependent on surface size. The universality of positive charge-driven exfoliation originates from the common intrinsic characteristics of electronic structures for layered materials. The positively doped charges that preferentially accumulate near the surface induce interlayer repulsion, leading to layer-by-layer exfoliation when repulsion surpasses interlayer van der Waals force. This strategy may open the possibility of producing diverse high-quality two-dimensional monolayers with a small number of defects toward large-scale manufacturing.

Automated summary

Based on the intrinsic characteristics of layered materials, this study introduces a universal principle for the production of intact monolayers through layer-by-layer exfoliation via positive charge doping. The universality of this exfoliation method stems from the common electronic structures of layered materials. This strategy opens the possibility of producing diverse high-quality two-dimensional monolayers on a large scale with minimal defects.