Wenqi Wang

Skin is the largest organ in the human body, and it is also the most important natural barrier. However, some accidents can cause skin damage. Bacterial infections and inflammatory reactions can hinder wound healing. Therefore, eliminating bacterial infections and regulating oxidative stress are essential. The use of antibiotics is no longer sufficient because of bacterial resistance. The development of new nanomaterials provides another way of thinking about bacterial drug resistance. In this study, bismuth selenide is modified with polyethylpyrrolidone to obtain a 2D nanomaterial with negligible toxicity and then added to a sodium polyacrylate hydrogel, which is nontoxic and has strong tissue adhesion and a weak antibacterial effect. To further enhance antibacterial performance, photothermal therapy is a good strategy. Under near‐infrared light, Bi ₂ Se ₃ /PAAS shows a strong bactericidal effect. Bi ₂ Se ₃ /PAAS hydrogels also have certain antioxidant effects and are used to remove excess free radicals from wound infections. The effective therapeutic effect of Bi ₂ Se ₃ /PAAS/NIR on methicillin‐resistant Staphylococcus aureus ( MRSA ) infection is further verified in animal models. Transcriptome analysis reveals that the Bi ₂ Se ₃ /PAAS hydrogel improves the function of vascular endothelial cells, regulates glucose and lipid metabolism, and promotes the healing of infected wounds.

In this article, a honeycomb vertical surrounding gate access transistor array scheme is proposed to further decrease the DRAM cell area with aggressively shrink bit line (BL) pitch and word line (WL) pitch adopting the ZigZag BL and WL air gap. To verify the process feasibility, process flow emulation is optimized by virtual fabrication with SEMulator3D®. Moreover, the ZigZag BL feasibility in lithography process is evaluated by optical proximity correction (OPC) simulation. In addition, the parasitic capacitance of BL and WL decrease 22.8% and 76.8%, respectively, as compared to reference paper. And the electrical properties of the proposed device are simulated by three-dimensional technology computer aided design (3D TCAD). The GIDL effect is prohibited through prolonging the drain extension and reducing its doping concentration. Finally, the surrounding gate transistor can achieve high on-state current (>30 μA) at V _g =1.5 V and off-state current below 0.1 fA at V _d = -0.2 V. These results are beneficial for the direction of pathfinding for increasing the density and decreasing the energy consumption of DRAM.

The nonradiative recombination induced by trap states at the surface and grain boundaries impedes the further increase of power conversion efficiency (PCE) and stability of perovskite solar cells (PSCs). Consequently, it is highly desirable to minimize the trap‐assisted nonradiative recombination in perovskite films. Here, an effective additive engineering strategy is reported where N‐succinimidyl 6‐maleimidohexanoate (denoted as NSMH) with multiple active sites and hydrophobic alkyl chains were incorporated for fully eliminating undercoordinated Pb²⁺ traps in perovskite films. It is revealed that improved crystallinity and reduced defect density are achieved, which is ascribed to the strong coordination interaction between the carbonyl groups at both sides of NSMH molecules and Pb²⁺. As a result, the NSMH‐modified device exhibits a champion PCE of 22.40% with negligible hysteresis, which is significantly higher than 20.67% of the control device. The unencapsulated modified device exhibits no degradation while the control device degrades to 82% of its initial PCE after storing for 1536 h in a relative humidity of 10–20% at room temperature in the dark.

Photonic crystal has been proved to manipulate light effectively and improve the performance of solar cells. In this paper, high-performance GaAs-based solar cells with photonic crystal were fabricated to decrease the dependence on the angle of incident light. Photoluminescence (PL) intensity of solar cells with photonic crystal reduced only 8% when the incident angle changed from 10° to 30°, while the PL intensity of the ordinary solar cells decreased 39% under the same condition. It manifests the photonic crystal can manipulate the incident light in turn reduce the dependence of incident light angle. Besides, the short circuit current of solar cells was increased by 32% after the photonic crystal was added. When the incident angle of light increased to 30° from 0°, the short circuit current of ordinary solar cell decreased 29.5%, while that of solar cell with photonic crystals reduced 12%. Correspondingly, the photoelectric conversion efficiency (PCE) of ordinary solar cells was reduced 31.2%. In contrast, solar cells with photonic crystal decreased only 11.5%. The enhancement factor of the PCE of solar cells with photonic crystal to that of ordinary solar cells increases from 1.26 to 1.6 as the incident angle rises to 30°from 0°. In summary, solar cells with photonic crystal are less sensitive to the incident angle and could absorb more light without angle limits, then increase the PCE. These solar cells with photonic crystals are promising in low-cost and high power conversion efficiency solar cell fields.

InAsSb/AlGaSb systems have potential in mid-wavelength infrared detection and laser fields. Thus, their heteroepitaxial crystal quality and heterointerface are of great importance. Herein, the quantum well structure based on InAs_0.8Sb_0.2/Al_0.2Ga_0.8Sb was grown by interruption with and without Sb₂ soaking methods by molecular beam epitaxy to optimize the interface quality and adjust the heterostructure strain. Narrow and well-defined satellite peaks in high-resolution x-ray diffraction patterns manifest good crystal quality of the sample with 15 s Sb₂ soaking interruption. The relaxation of sample A without Sb₂ soaking interruption is ∼23% calculated by the reciprocal space mappings, while there is no relaxation found in sample B with 15 s Sb₂ soaking. High-resolution transmission electron microscopy and energy-dispersive spectroscopy were carried out. They showed sharp and coherent heterointerfaces generated by adding interruptions with an Sb₂ overpressure before and after InAsSb layer growth. Furthermore, the atomic force microscopy images of a 5 × 5 μm² scan area show that the surface of sample B with Sb₂ soaking contains atomic steps with a root-mean-square roughness of 1.44 Å. The photoluminescence peaks of the samples located in the range of 3–4 µm show that these InAsSb/AlGaSb material systems have potential applications in mid-wavelength optoelectrical devices.

Efficient asymmetric alkylation of β,γ-unsaturated carboxylic acids without prior functionalization is enabled by chiral lithium amides. Enantioselectivity is imparted by a putative mixed lithium amide–enediolate aggregate that acts a traceless auxiliary formed in situ, allowing for a direct asymmetric alkylation and a simple recovery of the chiral reagent.