The controllable large‐area growth of single‐crystal vertical heterostructures based on 2D transition metal dichalcogenides (TMDs) remains a challenge. Here, large‐area vertical MoS2/WS2 heterostructures are synthesized using single‐step confined‐space chemical vapor epitaxy. The heterostructures can evolve into two different kinds by switching the H2 flow on and off: MoS2/WS2 heterostructures with multiple WS2 domains can be achieved without introducing the H2 flow due to the numerous nucleation centers on the bottom MoS2 monolayer during the transition stage between the MoS2 and WS2 monolayer growth. In contrast, isolated MoS2/WS2 heterostructures with single WS2 domain can be obtained with introducing the H2 flow due to the reduced nucleation centers on the bottom MoS2 monolayer arising from the hydrogen etching effect. Both the two kinds of the vertical MoS2/WS2 heterostructures feature high quality. The photodetectors based on the isolated MoS2/WS2 heterostructures exhibit a high responsivity of 68 mA W−1 and a short response time of 35 ms. This single‐step chemical vapor epitaxy can be used to synthesize vertical MoS2/WS2 heterostructures with high production efficiency. The new epitaxial growth approach may open new pathways to fabricate large‐area heterostructures made of different 2D TMDs monolayers of interest to electronics, optoelectronics, and other applications.

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With an 11Ah LiMn2O4 battery as the object of study, through disassembling the battery after normal charge and normal discharge as well as over-charge and over-discharge, and using such methods as x-ray diffraction and scanning electron microscope, this study explores the micro-changes that happened to the material for the anode and cathode of this lithium battery after over-charge and over-discharge, and provides the measures to prevent batteries from charge and discharge, so as to avoid potential safety problems during the use of lithium batteries.

The methods of examining and evaluating the consistency among batteries in a set are mostly meant for the batteries in a conventional application environment. Therefore, this article has studied the influence of C-rates on the consistency among batteries in a set in a low-temperature environment, as well as the regular pattern of changes in charging and discharging currents, providing reference data for the correct use of batteries in a low-temperature environment, and establishing a research base for the improvement on the performance of batteries.