Twisted bilayer graphene (tBLG) has gained significant attention due to its unique physical and electronic properties. However, efficient fabrication of high-quality tBLG with diverse twist angles is crucial to expedite research on angle-dependent physics and potential applications. In this study, an intercalation strategy utilizing organic molecules, such as 1,2-dichloroethane, is developed to weaken the interlayer interaction and induce slide or rotation of the topmost graphene layer for tBLG fabrication. The proportion of tBLGs in the resulting 1,2-dichloroethane-treated BLG (BLG) reaches up to 84.4% for twist angles ranging from 0° to 30°, surpassing previously reported methods using chemical vapor deposition (CVD). Moreover, the twist angle distribution is not uniform and tends to concentrate in the ranges of 0-10° and 20-30°. This facile and rapid intercalation-based methodology provides a practical solution for studying angle-dependent physics and advancing the utilization of twisted two-dimensional materials.

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http://dx.doi.org/10.1021/acs.nanolett.3c00560DOI Listing

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