High contact resistance of transition-metal dichalcogenide (TMD)-based devices is one of the bottlenecks that limit the application of TMDs in various domains. Contact resistance of TMD-based devices is strongly related to the interface chemistry and band alignment at the contact metal/TMD interfaces. To understand the metal/MoS 2 interface chemistry and band alignment, Ni and Ag metal contacts are deposited on MoS 2 bulk and chemical vapor deposition bilayer MoS 2 (2L-MoS 2 ) film samples under ultrahigh vacuum (∼3 × 10 −11 mbar) and high vacuum (∼3 × 10 −6 mbar) conditions. X-ray photoelectron spectroscopy is used to characterize the interface chemistry and band alignment of the metal/MoS 2 stacks. Ni forms covalent contact on MoS 2 bulk and 2L-MoS 2 film by reducing MoS 2 to form interfacial metal sulfides. In contrast, van der Waals gaps form at the Ag/MoS 2 bulk and Ag/ 2L-MoS 2 film interfaces, proved by the absence of an additional metal sulfide chemical state and the detection of Ag islands on the surface. Different from other metal/MoS 2 systems studied in this work, Ag shows potential to form an Ohmic contact on MoS 2 bulk regardless of the deposition ambient. Fermi levels (E F 's) are pinned near the intrinsic E F of the 2L-MoS 2 film with high defect density regardless of the work function of the metal, which highlights the impact of substrate defect density on the E F pinning effect and contact resistance.

Because of the variability of the RLN and ITA and the complicated relationship between them, it is necessary to dissect and recognize the RLN to avoid mistaking, ignoring, and misligating of the nerve before ligating the ITA.

A simple AgI‐mediated direct difluoromethylation reaction of activated alkenes by using TMSCF2COOEt (TMS = trimethylsilyl) under mild reaction conditions has been described. This reaction tolerates a variety of functional groups and allows for a highly efficient synthesis of various difluoro‐containing oxindoles. Mechanistic investigations indicate that a difluoromethyl radical initiated the cascade sequence by undergoing an addition reaction to the alkene.

Molybdenum disulfide, a two-dimensional transition metal dichalcogenide, was analyzed using in situ x-ray photoelectron spectroscopy (XPS). The XPS spectra obtained from a fresh surface which was exfoliated and annealed in ultrahigh vacuum include a survey scan, high resolution spectra of O 1s, C 1s, Mo 3d, S 2s, S 2p, Mo 3p, Mo 4p, S 3s, and the valence band. Quantitative analysis indicates a sulfur deficient surface composition of MoS1.8, and impurities were below the XPS detection limit.

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