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In crystalline silicon (c‐Si) solar cells, the hole transport layer (HTL) made of high oxygen content MoOx (x > 2.85, H‐MoOx) evaporating from molybdenum trioxide is not ideal due to low optical bandgap and interface reaction effects. This limits the power conversion efficiency (PCE) and stability of c‐Si solar cells. To improve this, low oxygen content MoOx (x < 2.85, L‐MoOx) with a wide bandgap of 3.87 eV, deposited using molybdenum dioxide (MoO2), is explored and implemented. The c‐Si/SiOx (FGA, forming gas annealing)/L‐MoOx heterojunction has a low contact resistivity of ≈15.06 mΩ cm2, which is almost one order of magnitude lower than that of c‐Si/SiOx(FGA)/H‐MoOx heterojunction. Using L‐MoOx as the HTL, a c‐Si solar cell based on the SiOx passivation layer shows a fill factor of 84.38% and PCE of 21.75%, representing the highest efficiency for MoOx‐based p‐type c‐Si solar cells. Scanning transmission electron microscopy results show that the L‐MoOx HTL effectively enhances the stability of c‐Si solar cells when exposed to air by reducing Ag and Si element diffusion into MoOx. This successful preparation of efficient and stable MoOx HTL films, while preserving their field‐effect passivation ability, provides valuable insights into the development of high‐performance HTL. [ABSTRACT FROM AUTHOR]

Engineering acid site spatial location of zeolite catalyst harbors tremendous potential to boost catalytic performance but still remains a grand challenge for aromatization reaction. Herein, we successfully manipulate acid site spatial location inside the ZSM‐5 channels to promote the hexane aromatization via the simple SiO2 coating treatment. Multi‐techniques demonstrated that the medium strong L acid in the channel originated from the Si(Al)OZn structure is mainly retained in the Zn/ZSM‐5‐Si catalyst by covering the acid sites outside the channel. Surprisingly, there is a good linear relationship between BTEX yield and this medium strong L acid content. Based on the reaction kinetics, in situ FT‐IR and theoretical calculations, it is found that the L acid with confinement effect served as the main active site could prominently enhance the cyclization of propene intermediate and the dehydrogenation of cycloalkane due to the strong affinity between the C/H and ZnOx, and control the desorption of BTEX (mainly benzene, toluene, ethylbenzene, and p‐xylene) by weakening the binding of hydrogen proton to π electrons. Compared with the ordinary Zn/ZSM‐5 catalyst, the yield of BTEX is increased by nearly 10%, and the Zn/ZSM‐5‐Si catalyst exhibits excellent anti coking deactivation ability. This strategy together with mechanistic results may pave the rational design of efficient Zn/ZSM‐5 catalysts for aromatization reaction. [ABSTRACT FROM AUTHOR]

Automatic License Plate detection and Recognition (ALPR) is a key problem in intelligent transportation systems with wide applications in traffic monitoring, electronic toll collection (ETC), intelligent parking lots (IPLs), and elsewhere. Although numerous methods have been proposed in the literature, it is still challenging to strike a good balance between the accuracy and efficiency of ALPR. In this paper, a novel end‐to‐end CNN‐based model is proposed, called Fast and Accurate Network with Feature Enhancement (FAFEnet), to jointly detect the license plates and recognize the characters with high accuracy and efficiency. Specifically, the FAFEnet model seamlessly integrates two CNN‐based models, namely the detection and recognition modules, into a unified framework to reduce accumulated errors and computational overheads in two separate steps. The detection module is a lightweight model with only seven convolutional layers yet achieves over 99.8% accuracy rates for license plate detection across all datasets. The recognition module utilizes two feature enhancement blocks to compensate and enhance the shallow character features extracted by the detection module. Furthermore, the joint optimization of detection and recognition modules exploits the feature association in two modules, and thus improves the prediction accuracy while reducing the execution time. Finally, extensive experimental results on several real‐world datasets demonstrate that FAFEnet outperforms all the competitors in terms of both accuracy and efficiency. [ABSTRACT FROM AUTHOR]

Polymeric room temperature phosphorescence (RTP) materials have attracted tremendous attentions owing to their excellent flexibility, easy processing, low cost, and good thermal stability. In this work, an improved strategy is proposed for ultralong RTP polymeric materials through copolymerizing the phosphor monomer with D (donor)−A (acceptor) structure and another monomer with ultrastrong multiple hydrogen bonds. A series of copolymers (P1–P4) containing different ratios of carbazole‐dibenzofuran (CDF) and ureidopyrimidinone (UPy) segments are successfully prepared. The obtained copolymers show ultralong phosphorescence lifetimes between 1.70 and 2.16 s with afterglow duration time between 15 and 17 s. The multiple hydrogen bonds of UPy groups can promote extremely intermolecular and intramolecular interactions, which immobilize the phosphors to prevent nonradiative transitions. Especially, these interactions lead to the copolymers can be robustly resistant to high temperature and humidity. Flexible and foldable anti‐counterfeiting with high temperature and humidity resistant features are achieved, which would be applied in practical special environments. [ABSTRACT FROM AUTHOR]

CsPbBr3, as an all‐inorganic perovskite, has attracted considerable research interest due to its excellent optoelectronic properties. However, because the electronic properties of CsPbBr3 are not satisfactory, the relatively low on/off ratio and long photoresponse time of CsPbBr3 devices limit further applications. In this work, a CsPbBr3 device with high performance is successfully fabricated through a simple process using a CsPbBr3 colloid, and the photoresponse performance of the device is investigated under different external factors. By inserting a thin HfO2 layer, CsPbBr3‐based heterostructure devices exhibit much better performances, including an enhanced photocurrent of ≈10 µA, a responsivity of 45.05 A W−1, a detectivity of 9.12 × 1010 Jones, an external quantum efficiency of 12445%, and rise/fall times of 600 µs/300 µs, respectively. A physical mechanism is proposed to explain the photoresponse property promotion in CsPbBr3 devices, which can be attributed to the tunneling effect between CsPbBr3 and Si through the thin HfO2 layer. More importantly, the optoelectrical properties of the proposed CsPbBr3/HfO2/Si heterostructure device can be modulated through both Vds and Vgs. This work offers a valuable strategy and a practical scheme that can be generalized to other perovskite and heterostructure devices. [ABSTRACT FROM AUTHOR]

Objectives: To compare the efficacy of pulsed high‐intensity focused ultrasound (PHIFU) versus continuous high‐intensity focused ultrasound (CHIFU) ablation at identical doses. Methods: Continuous and pulsed HIFU (1200 J) at duty cycles (DCs) of 60% and 20% were examined for their capacity to ablate bovine liver tissue in vitro and rabbit liver tissue in vivo. After ablation, grayscale changes and pathologic characteristics were observed or measured, and the tissue necrosis volume, energy efficiency factor, and average grayscale density were calculated. Results: The pulsed mode generated greater liquefaction necrosis. An inconspicuous grayscale change was observed for PHIFU at a DC of 20% in some samples, which appeared as an elliptical cavity. The energy efficiency factor of PHIFU at a DC of 60% was significantly lower than that of CHIFU, as observed both in vitro and in vivo (P <.05). The grayscale value and average grayscale density in response to CHIFU were significantly greater than those in response to PHIFU (60% or 20%; P <.05). Histopathologic analysis revealed liquefaction necrosis in all PHIFU groups. Conclusions: At identical doses, compared with CHIFU, a single session of PHIFU can generate liquefaction necrosis and at a higher DC can improve ablation efficiency. This increased efficacy of PHIFU may involve enhancement of tissue destruction by cavitation effects and a reduction in the obstruction effect of endogenous microbubbles through cavitation effects or a more effective diffusion of heat. [ABSTRACT FROM AUTHOR]