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The anodized aluminum oxide prepared by anodizing is the core of aluminum electrolytic capacitors, and its quality determines the performance of aluminum electrolytic capacitors. The traditional direct current (t‐DC) anodizing method commonly used in industrial production today with low current density has the problems of low anodizing efficiency, poor crystallinity, and high formation constants of the oxide film. However, high current density direct current anodizing has the problems of severe defects of the oxide film and much thermal dissolution of aluminum foil. Herein, the dual‐phase enabled sinusoidal current (DESC) anodizing method is proposed for the preparation of 200 V anodized aluminum foil with much higher efficiency and performance. After testing, it is found that the alumina prepared by the DESC method has higher crystallinity and fewer defects. Consequently, the specific capacitance of the DESC sample is 23% greater than that of the t‐DC anodized sample, while the former displays a lower loss angle tangent and leakage current. Meanwhile, DESC anodizing takes 60% time less than t‐DC anodizing due to its high current density. The DESC anodizing method has been identified as a promising avenue for further investigation, exhibiting high efficiency and performance. [ABSTRACT FROM AUTHOR]

Poly(3,4‐ethylenedioxythiophene):poly(styrene sulfonate) (PEDOT:PSS), a conductive polymer dispersion, is widely used in cathodes of solid electrolytic capacitors. However, it still suffers from performance limitations when used at high frequencies, and its withstand voltage must be improved. Herein, impregnation drying introduces a polyvinyl alcohol (PVA) coating onto alumina, which regulates the interface between the PEDOT:PSS cathode and alumina. The equivalent series resistance (ESR) of the capacitor is significantly reduced, whereas the withstand voltage is slightly improved. This study demonstrates that the presence of PVA enhances the wettability of PEDOT:PSS dispersions on alumina surfaces. Changes in the infrared peak positions of the OH and SO3H groups following the mixing of the PVA and PEDOT:PSS films, along with alterations in the thermal decomposition temperature, indicate the occurrence of crosslinking. Theoretical calculations demonstrate the presence of hydrogen bonds between the OH groups in PVA and the SO3H groups of PEDOT:PSS. Interface modulation effectively improves capacitor performance, as the capacitance ratio of capacitors with 400 V level withstand voltages increases from 97.35% to 98.85%, and the ESR at 100 kHz is significantly reduced by ≈40%. This study provides a valuable reference for the preparation of high‐performance solid electrolytic capacitors. [ABSTRACT FROM AUTHOR]

Mn(II)-doped cesium lead halide perovskite (CsPbX3 (X = Cl, Br, I)) quantum dots (QDs) have attracted a lot of attention from researchers attributed to their bright orange light emission. However, defects such as inefficient energy transfer and instability have hindered the commercial application of the material. Here, we propose a convenient core–shell coating strategy to epitaxially grow a CsPb2X5 shell on Mn-doped CsPbX3 surfaces by controlling the reaction time and precursor ratio. Meanwhile, density-functional theory (DFT) calculations indicate that a typical type-I heterojunction is formed between the CsPb(Cl/Br)3 cores and the CsPb2(Cl/Br)5 shell, which improves the energy transfer efficiency from an exciton to Mn2+. The obtained Mn-doped CsPb(Cl/Br)3@CsPb2(Cl/Br)5 core–shell materials exhibit enhanced optical properties and excellent water/thermal stability. Subsequently, the white light-emitting diode prepared from the composites shows a high luminescence efficiency of 127.21 lm W−1, and the PL intensity is still maintained above 95% after 24 h of continuous operation. [ABSTRACT FROM AUTHOR]

The commercial viability of fluorescent materials is critically contingent on their thermal stability. Recent interest has converged on lead-free double perovskites (DPs), renowned for their optical properties mirroring those of traditional lead-based counterparts and superior atmospheric stability. However, these materials encounter significant fluorescence degradation in thermal environments, a challenging scenario given the high temperatures endemic to the surfaces of optoelectronic devices during prolonged operation, detrimentally impacting the fluorescent attributes of lead-free DPs. To address this challenge, in situ synthesis of lead-free DP nanocrystals (NCs) within KIT-6 mesoporous molecular sieves is proposed, yielding Cs2AgIn0.98Bi0.02Cl6@KIT-6 NCs with enhanced optical qualities. Experimental results demonstrate a marked enhancement in the fluorescence thermal stability of these NCs, attributed to the protective KIT-6 shell layer. Subjected to high power operation (100 mA) for 270 minutes, the fabricated orange light-emitting diode (LED) device maintained 80% of initial luminous efficiency, despite the resultant elevated surface temperature of 326.8 K. Therefore, this novel in situ assembly approach significantly bolsters the operational stability of lead-free DPs, paving the way for their potential commercial applications. [ABSTRACT FROM AUTHOR]

Pb‐free double‐perovskite (DP) scintillators are highly promising candidates for X‐ray imaging because of their superior optoelectronic properties, low toxicity, and high stability. However, practical applications require Pb‐free DP crystals to be ground and mixed with polymers to produce scintillator films. Grinding can compromise film uniformity and optical properties, thereby affecting imaging resolution. In this study, an in situ fabrication strategy is proposed to facilitate the crystalline growth of Pb‐free Cs2AgInxBi1‐xCl6 micron sheets in polymethyl methacrylate in a single step. By adjusting the In3+/Bi3+ ratio, Cs2AgIn0.9Bi0.1Cl6/PMMA composite films (CFs) with excellent scintillation properties are obtained, including a light yield of up to 32000 photons per MeV and an X‐ray detection limit of 87 nGyairs−1. This strategy also enabled the production of large Cs2AgIn0.9Bi0.1Cl6/PMMA CFs, which demonstrated favorable flexibility and stability, fabricating products with advanced eligibility for commercial applications. The CFs exhibited outstanding performances in X‐ray imaging, producing high‐resolution structures and providing a new avenue for the development of Pb‐free DP materials in fields such as medical imaging and safety detection. [ABSTRACT FROM AUTHOR]