CC BY 4.0 UnportedLy, Thuc HuePerello, David J.Zhao, JiongDeng, QingmingKim, HyunHan, Gang HeeChae, Sang HoonJeong, Hye YunLee, Young Hee2018-06-072019-06-282016https://doi.org/10.34657/4987https://oa.tib.eu/renate/handle/123456789/1497Grain boundaries in monolayer transition metal dichalcogenides have unique atomic defect structures and band dispersion relations that depend on the inter-domain misorientation angle. Here, we explore misorientation angle-dependent electrical transport at grain boundaries in monolayer MoS2 by correlating the atomic defect structures of measured devices analysed with transmission electron microscopy and first-principles calculations. Transmission electron microscopy indicates that grain boundaries are primarily composed of 5–7 dislocation cores with periodicity and additional complex defects formed at high angles, obeying the classical low-angle theory for angles <22°. The inter-domain mobility is minimized for angles <9° and increases nonlinearly by two orders of magnitude before saturating at ∼16 cm2 V−1 s−1 around misorientation angle≈20°. This trend is explained via grain-boundary electrostatic barriers estimated from density functional calculations and experimental tunnelling barrier heights, which are ≈0.5 eV at low angles and ≈0.15 eV at high angles (≥20°).application/pdfapplication/pdfenghttps://creativecommons.org/licenses/by/4.0/620Atomic and molecular physicsElectronic properties and devicesNanoscience and technologyArticle