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Two-dimensional van der Waals heterojunctions consisted of p–n-type semiconductors have been rapidly developed owing to their built-in electric field which can facilitate the separation of photogenerated electron–hole pairs and properties like current rectification and negative differential transconductance. Benefitting from these advantages, we have prepared an air-stable multifunctional p-tellurium (Te)/n-MoS2 heterostructure working both as a self-driven broadband photodetector and as an optically switchable complementary metal-oxide-semiconductor inverter. For photodetection, this device exhibits wavelength-modulated positive/negative optical response with large responsivity (1.51 A/W at 520 nm and 642.92 mA/W at 1550 nm, Vds = 0 V) and fast response speed, showcasing its prospects for optical encoding communication. Moreover, the device has been demonstrated to function as an inverter that will be shut down by illumination. Our multifunctional device possesses the compactness of integrated modules, widens the application scope of Te-based heterojunctions, and provides a reference for the application of Te-based devices in the field of integrated circuits. [ABSTRACT FROM AUTHOR]

Membranes with precise Li+/Na+ and Li+/K+ separations are imperative for lithium extraction from brine to address the lithium supply shortage. However, achieving this goal remains a daunting challenge due to the similar valence, chemical properties, and subtle atomic‐scale distinctions among these monovalent cations. Herein, inspired by the strict size‐sieving effect of biological ion channels, a membrane is presented based on nonporous crystalline materials featuring structurally rigid, dimensionally confined, and long‐range ordered ion channels that exclusively permeate naked Li+ but block Na+ and K+. This naked‐Li+‐sieving behavior not only enables unprecedented Li+/Na+ and Li+/K+ selectivities up to 2707.4 and 5109.8, respectively, even surpassing the state‐of‐the‐art membranes by at least two orders of magnitude, but also demonstrates impressive Li+/Mg2+ and Li+/Ca2+ separation capabilities. Moreover, this bioinspired membrane has to be utilized for creating a one‐step lithium extraction strategy from natural brines rich in Na+, K+, and Mg2+ without utilizing chemicals or creating solid waste, and it simultaneously produces hydrogen. This research has proposed a new type of ion‐sieving membrane and also provides an envisioning of the design paradigm and development of advanced membranes, ion separation, and lithium extraction. [ABSTRACT FROM AUTHOR]

Rechargeable sodium–oxygen batteries (NaOBs) are receiving extensive research interests because of their advantages such as ultrahigh energy density and cost efficiency. However, the severe failure of Na metal anodes has impeded the commercial development of NaOBs. Herein, combining in situ synchrotron X‐ray computed tomography (SXCT) and other complementary characterizations, a novel electro‐chemo‐mechanical failure mechanism of sodium metal anode in NaOBs is elucidated. It is visually showcased that the Na metal anodes involve a three‐stage decay evolution of a porous Na reactive interphase layer (NRIL): from the initially dot‐shaped voids evolved into the spindle‐shaped voids and the eventually‐developed ruptured cracks. The initiation of this three‐stage evolution begins with chemical‐resting and is exacerbated by further electrochemical cycling. From corrosion science and fracture mechanics, theoretical simulations suggest that the evolution of porous NRIL is driven by the concentrated stress at crack tips. The findings illustrate the importance of preventing electro‐chemo‐mechanical degradation of Na anodes in practically rechargeable NaOBs. [ABSTRACT FROM AUTHOR]

Helicobacter pylori (HP), a common microanaerobic bacteria that lives in the human mouth and stomach, is reported to infect ≈50% of the global population. The current diagnostic methods for HP are either invasive, time‐consuming, or harmful. Therefore, a noninvasive and label‐free HP diagnostic method needs to be developed urgently. Herein, reduced graphene oxide (rGO) is composited with different metal‐based materials to construct a graphene‐based electronic nose (e‐nose), which exhibits excellent sensitivity and cross‐reactive response to several gases in exhaled breath (EB). Principal component analysis (PCA) shows that four typical types of gases in EB can be well discriminated. Additionally, the potential of the e‐nose in label‐free detection of HP infection is demonstrated through the measurement and analysis of EB samples. Furthermore, a prototype of an e‐nose device is designed and constructed for automatic EB detection and HP diagnosis. The accuracy of the prototype machine integrated with the graphene‐based e‐nose can reach 92% and 91% in the training and validation sets, respectively. These results demonstrate that the highly sensitive graphene‐based e‐nose has great potential for the label‐free diagnosis of HP and may become a novel tool for non‐invasive disease screening and diagnosis. [ABSTRACT FROM AUTHOR]

Atomicity violation bugs are a frequent problem in concurrency. Because of the unpredictable nature of thread interleaving, most current methods are unable to differentiate between harmful and benign atomicity violations. This makes it challenging to determine the existence of an actual bug. This paper presents a method for detecting atomicity violation bugs in programs based on user interaction. First, UserTrack matches access interleaving patterns to identify all potential violations. We then verify the programmer's atomicity intent between two logical access operations on the same thread and filter out some candidates. Finally, a user interaction mechanism checks the paths that do not produce atomicity violations when threads are interleaved. Our method focuses on a small number of interesting states and interleavings, while allowing the programmer to impose constraints on thread interleavings and explore all executions that satisfy these constraints. We continuously gather information through user feedback results and detect atomicity violation bugs that truly go against the programmer's intent. We evaluated the method using benchmark tests, which demonstrated the effectiveness of UserTrack in detecting atomicity violations. [ABSTRACT FROM AUTHOR]

Morphological control of metal-organic frameworks (MOFs) at the micro/nanoscopic scale is critical for optimizing the electrochemical properties of them and their derivatives. In this study, manganese organic phosphate (Mn-MOP) with three distinct two-dimensional (2D) morphologies was synthesized by varying the molar ratio of Mn2+ to phenyl phosphonic acid, and one of the morphologies is a unique palm leaf shape. In addition, a series of 2D Mn-MOP derivatives were obtained by calcination in air at different temperatures. Electrochemical studies showed that 2D Mn-MOP derivative calcined at 550 °C and exhibited a superior specific capacitance of 230.9 F g−1 at 0.5 A g−1 in 3 M KOH electrolyte. The aqueous asymmetric supercapacitor and the constructed flexible solid-state device demonstrated excellent rate performance. This performance reveals the promising application of 2D Mn-MOP materials for energy storage. [ABSTRACT FROM AUTHOR]