The discovery of graphene has triggered the research on 2D layer structured materials. Among many 2D materials, semiconducting transition metal dichalcogenides (TMDs) are widely considered to be the most promising ones due to their excellent electrical and optoelectronic characteristics. Tungsten disulfide (WS2) is a kind of such TMDs with fascinating properties, such as the high carrier mobility, appropriate band gap, strong light–matter interaction with the large light absorption coefficient, very large exciton binding energy, large spin splitting, and polarized light emission. All these interesting properties can make the 2D WS2 being highly favorable for applications in memristors, light‐emitting devices, optical modulators, and many others. Here, the comprehensive review on the properties, vapor phase synthesis, electronic and optoelectronic applications of 2D WS2 is presented. This review does not only serve as a design guideline to elevate the material quality of 2D WS2 films via enhanced synthesis approaches, but also provides valuable insights to various strategies to improve their device performances. With the fast development of wafer‐scale synthesis methods and novel device structures, 2D WS2 can undoubtedly be a rising star for the next‐generation devices in the near future.

We determined the role of endogenous hydrogen sulfide (H₂S) in cerebral vasodilation/hyperemia and early BBB disruption following ischemic stroke. A cranial window was prepared over the left frontal, parietal and temporal cortex in mice. Transient focal cerebral Ischemia was induced by directly ligating the middle cerebral artery (MCA) for two hours. Regional vascular response and cerebral blood flow (CBF) during ischemia and reperfusion were measured in real time. Early BBB disruption was assessed by Evans Blue (EB) and sodium fluorescein (Na-F) extravasation at 3 hours of reperfusion. Topical treatment with DL-propargylglycine (PAG, an inhibitor for cystathionine γ-lyase (CSE)) and aspartate (ASP, inhibitor for cysteine aminotransferase/3-mercaptopyruvate sulfurtransferase (CAT/3-MST)), but not O-(Carboxymethyl)hydroxylamine hemihydrochloride (CHH, an inhibitor for cystathionine β-synthase (CBS)), abolished postischemic cerebral vasodilation/hyperemia and prevented EB and Na-F extravasation. CSE knockout (CSE-/-) reduced postischemic cerebral vasodilation/hyperemia but only inhibited Na-F extravasation. An upregulated CBS was found in cerebral cortex of CSE-/- mice. Topical treatment with CHH didn’t further alter postischemic cerebral vasodilation/hyperemia, but prevented EB extravasation in CSE-/- mice. In addition, L-cysteine-induced hydrogen sulfide (H2S) production similarly increased in ischemic side cerebral cortex of control and CSE-/- mice. Our findings suggest that endogenous production of H2S by CSE and CAT/3-MST during reperfusion may be involved in postischemic cerebral vasodilation/hyperemia and play an important role in early BBB disruption following transient focal cerebral ischemia.