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We report on the synthesis of self-intercalated Nb1+xSe2 thin films by molecular beam epitaxy. Nb1+xSe2 is a metal-rich phase of NbSe2 where additional Nb atoms populate the van der Waals gap. The grown thin films are studied as a function of the Se to Nb beam equivalence pressure ratio (BEPR). X-ray photoelectron spectroscopy and x-ray diffraction indicate that BEPRs of 5:1 and greater result in the growth of the Nb1+xSe2 phase and that the amount of intercalation is inversely proportional to the Se to Nb BEPR. Electrical resistivity measurements also show an inverse relationship between BEPR and resistivity in the grown Nb1+xSe2 thin films. A second Nb-Se compound with a stoichiometry of ∼1:1 was synthesized using a Se to Nb BEPR of 2:1; in contrast to the Nb1+xSe2 thin films, this compound did not show evidence of a layered structure.

Tailoring the electrical transport properties of two-dimensional transition metal dichalcogenides can enable the formation of atomically thin circuits. In this work, cyclic hydrogen and oxygen plasma exposures are utilized to introduce defects and oxidize MoS₂in a controlled manner. This results in the formation of sub-stochiometric MoO_3−x, which transforms the semiconducting behavior to metallic conduction. To demonstrate functionality, single flakes of MoS₂were lithographically oxidized using electron beam lithography and subsequent plasma exposures. This enabled the formation of atomically thin inverters from a single flake of MoS₂, which represents an advancement toward atomically thin circuitry.

Contamination of high‐touch surfaces with infected droplets of bodily secretions is a known route of virus transmission. Copper surfaces have been reported to inactivate human coronaviruses after several minutes, via the release of Cu cations. Utilization of copper alloys for high‐touch surfaces can be a pivotal preemptive strategy for preventing the next pandemic. Understanding the true efficacy by which copper, and copper alloys, inactivate the virus under realistic conditions is essential for tuning intrinsic alloy features such as composition, grain orientation, and surface attributes, to optimize for antiviral function. However, virus inactivation measurements depend on the presence of an assay media (AM) solution as a carrier for the virus, and its effects on the surface properties of pure copper that regulate oxidative copper release are previously unknown. Herein, these properties and the influence of AM on the efficacy of virus inactivation occurring on the surface of pure copper are investigated. The process is uncovered by which a five‐fold decrease in virus half‐life is observed in simulated real‐life conditions, relative to exposure to traditional AM. The investigation highlights the notion that virus inactivation on copper surfaces may be significantly more effective than previously thought.