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The weak dielectric properties and the lack of magnetic loss of manganese-based absorbers are obstructed as the new generation of electromagnetic wave absorption (EMA) materials applying in microelectronic devices. Herein, the sulfuration and subsequent compounding strategies have been employed to enhance the EMA performance of multi-shell nanosphere-shaped Mn 2 O 3 materials. With the narrow bandgap, the as-obtained MnS possesses reinforced electrical conductivity, which is conducive to conductivity loss. More importantly, the presence of potential difference between different phases will form space charge region at the heterogeneous interface, thus favoring interfacial polarization. Additionally, the improvement of magnetic loss is attributed to the presence of Co 3 O 4 nanoparticles. Consequently, the composites present enhanced EMA performance than original Mn 2 O 3 . Specifically, the minimum reflection loss of as-prepared composites is −51.4 dB at the thickness of 1.8 mm and the broad effective absorption bandwidth reaches 6.2 GHz at 1.9 mm. The low matching thickness and high absorption efficiency in this work can provide a convincing reference when designing distinguished manganese-based absorbers.

Through‐space charge transfer (TSCT) polymers are an attractive class of luminescent polymers with spatial donor/acceptor architecture and thermally activated delayed fluorescence effect, different from conventional luminescent polymers with conjugated donor‐acceptor structure and through‐bond charge transfer emission. Their emission comes from the intramolecular charge transfer by through‐space pathway because the donor and acceptor segments are spatially proximate to each other in each repeating unit but are physically separated by nonconjugated polymer backbone. In this review, recent advances in TSCT polymers with linear, bottlebrush, and dendritic architectures are presented, with the focus on their molecular design, photophysical behavior, and device performance. We hope that this review shall provide a useful insight of new luminescent polymers with TSCT effect for use in solution‐processed organic light‐emitting diodes. Through‐space charge transfer (TSCT) polymers, with spatial donor/acceptor architecture and thermally activated delayed fluorescence effect, represent an attractive approach toward efficient solution‐processed organic light‐emitting diodes. In this review, recent advances in TSCT polymers with linear, bottlebrush, and dendritic architectures are presented, with the focus on their molecular design, photo‐physical behavior, and device performance.

Eleven unusual precursors were observed in the initial stage of a classical triggered lightning event, which was performed on CMA‐FEBLS in the summer of 2024. The amplitudes of these unusual leaders exceeded 300 A, with pulse intervals from 30 to 200 ms, while their initiation height was only about 30 m. Once these attempted leaders surpassed 250 m, they resumed the development pattern of conventional precursors. The analysis suggested that the occurrence of unusual precursors is related to the existence of the space charge layer, as the event occurred under thunderstorm conditions with sparse natural discharges, which facilitated its accumulation. When subjected to airflow or precipitation, the space charges were susceptible to localized abrupt diminution or dissipation. Such changes induced anomalous enhancements in the electric field intensity at the wire's tip as it traversed through the space charge region, ultimately leading to the occurrence of unusual precursors.

Solid-state lithium metal batteries (SSLBs) contain various kinds of interfaces, among which the solid electrode|solid electrolyte (ED|SE) interface plays a decisive role in the battery’s power density and cycling stability. However, it is still lack of comprehensive knowledge and understanding about various interfacial physical/chemical processes so far. Although tremendous efforts have been dedicated to investigate the origin of large interfacial resistance and sluggish charge (electron/ion) transfer process, many scientific and technological challenges still remain to be clarified. In this review, we detach and discuss the critical individual challenge, including charge transfer process, chemical and electrochemical instability, space charge layers, physical contact and mechanical instability. The fundamental concepts, individual effects on the charge transfer and potential solutions are summarized based on material’s thermodynamics, electrode kinetics and mechanical effects. It is anticipated that future research should focus on quantitative analysis, modeling analysis and in-situ microstructure characterizations in order to obtain an efficient manipulation about the complex interfacial behaviors in all solid-state Li batteries.

We investigate the impact of space-charge effects on the ponderomotive interaction between electron pulses and laser fields in the context of ponderomotive lenses. We present a numerical framework that self-consistently models both the ponderomotive electron–light interaction and the electron–electron Coulomb repulsion within multi-electron, ultrashort pulses. By comparing these simulations with a single-electron, wave-based description, we demonstrate that space-charge effects significantly degrade the performance of ponderomotive lenses for electron beam shaping and focusing. Our results show that this deterioration appears already at very low bunch charges, setting clear limits for the manipulation of dense electron pulses with ponderomotive optics.

In this study, the space charge characteristics in the polycyclic aromatic compounds doped cross-linked polyethylene (XLPE) composite were analysed by integration current (Q(t)) method and quantum chemical calculation. Experimentally, the space charge behaviours of XLPE composites modified by the three selected polycyclic aromatic compounds during polarisation and depolarisation process at 25 and 80°C were measured by Q(t) method, respectively. The energy levels and 3D potential distributions of the three polycyclic aromatic compounds were calculated by density functional theory. The experimental and calculation results indicate that the polycyclic aromatic compound C with deep carrier traps and stronger polarity exhibits outstanding ability to reduce space charge injection than the others at both 25 and 80°C. Generally, 4,4′-bis (dimethyl amino) benyil has great potential as the organic additive for DC cable insulation from the view of space charge suppression.

Three kinds of through-space charge transfer (TSCT) blue polymers containing non-conjugated polystyrene backbone together with spatially-separated acridan donor and oxygen-bridged triphenylboron acceptors having different substituents of tert -butyl, hydrogen and fluorine are designed and synthesized. The designed TSCT blue polymers possess photoluminescence quantum yields up to 70% in solid-state film, single-triplet energy splitting below 0.1 eV, and typical thermally activated delayed fluorescence (TADF) effect. Meanwhile, the resulting polymers exhibit aggregation-induced emission (AIE) effect with emission intensity increased by up to ~27 folds from solution to aggregation state. By changing the substituent of acceptors to tune the charge transfer strength, blue emission with peaks from 444 to 480 nm can be realized for the resulting polymers. Solution-processed organic light-emitting diodes based on the polymers exhibit excellent device performance with Commission Internationale de L’Eclairage (CIE) coordinates of (0.16, 0.27), together with the maximum luminous efficiency of 30.7 cd A -1 and maximum external quantum efficiency of 15.0%, which is the best device efficiency for blue TADF polymers.

The molecular engineering of fluorescent organic/polymeric materials, specifically those emitting in the deep red to near-infrared spectrum, is vital for advancements in optoelectronics and biomedicine. Perylene diimide (PDI), a well-known fluorescent scaffold, offers high thermal and photophysical stability but suffers from fluorescence quenching in solid or aggregate states due to intense π - π interactions. To mitigate this, simple and versatile methods for strong PDI aggregate emission without extensive synthetic demands are highly desirable but still lacking. Here, we report a straightforward strategy to enhance the solid-state emission of PDI by introducing certain degree of through-space charge transfer (TSCT) via controlled radical polymerization, which can efficiently distort the typical face-to-face PDI stacking, enabling greatly enhanced deep red emission. This is achieved by growing electron-donating star-shape styrenic (co)polymers from a multidirectional electron-accepting PDI initiator. The incorporation of polycyclic aromatic monomers further shifted the emission into the near-infrared region, albeit with a reduced intensity. Overall, the emission of the PDI-based TSCT polymers can be systematically manipulated by leveraging the balance between PDI stacking and the TSCT degree, as confirmed by both experimental study and theoretical calculations. Our approach circumvents complex synthetic procedures, offering highly emissive materials with large Stokes shifts and showing broad potential for optoelectronic technology.

A nitridation treatment technology with a urea/ammonia complex nitrogen source improved resistive switching property in HfO 2 -based resistive random access memory (RRAM). The nitridation treatment produced a high performance and reliable device which results in superior endurance (more than 10 9 cycles) and a self-compliance effect. Thus, the current conduction mechanism changed due to defect passivation by nitrogen atoms in the HfO 2 thin film. At a high resistance state (HRS), it transferred to Schottky emission from Poole-Frenkel in HfO 2 -based RRAM. At low resistance state (LRS), the current conduction mechanism was space charge limited current (SCLC) after the nitridation treatment, which suggests that the nitrogen atoms form Hf–N–Ox vacancy clusters (V o + ) which limit electron movement through the switching layer.

Epoxy resin has been used to cast the core of the dry‐type high voltage direct current bushings and can accumulate space charge under high electric fields at high temperatures, which is believed to be a potential threat to the safe operation of dry bushings, especially under polarity reversal. In this study, results of a study of the evolution of space charge and electric field distribution in epoxy resin, under polarity reversal at 10 and 20 kV/mm, and at temperatures between 40 and 100°C, are presented. The results show that the space charge dynamics in epoxy resin during the test were different at various temperatures. At temperatures no more than 60°C, space charge accumulation within the samples was not obvious. Instead, a low‐frequency dielectric relaxation process maybe occurs during the polarity reversal, which made the charge peaks on the electrodes after the reversal were slightly smaller than those before the reversal. At temperatures no less than 80°C, considering that the applied electric field has little effect on the barrier reductions of the traps within the samples, the space charge dynamics were mainly governed by a thermally activated process, and the depths of the deepest occupied traps were obtain by analysing the transient processes.