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Sodium metal batteries are promising next‐generation energy storage technology by using energy‐dense and affordable Na metal anodes, yet suffering uncontrollable Na dendritic growth issues. Herein, Au nanoparticle@hollow amorphous carbon tube yolk/shell arrays (Au/HCT‐CC) is rationally designed on carbon cloth as a dynamic host. In situ transmission electron microscopy observations reveal a regulated dendrite‐free Na metal plating/stripping within the Au/HCT‐CC host. The self‐confinement of Na metal deposition in the hollow carbon can further stabilize the electrolyte/electrode interface and homogenize Na ion flux, as evidenced by rigorous experimental and theoretical characterizations, thus successfully accommodating the hurdles to Na metal anodes. When cycling in half cells, the Au/HCT‐CC electrodes deliver remarkably high coulombic efficiencies (CEs) of 99.96% over 2200 h at 5 mA cm−2. The high CE of 99.54% is preserved even under harsh cycling conditions of 10 mA cm−2 and 20 mAh cm−2 for 250 cycles. These values rival the state‐of‐the‐art electrochemical performance for Na metal anodes in literature. Finally, the practical feasibility of the new anode is demonstrated by cycling in Na3V2(PO4)3@C||Na‐Au/HCT‐CC full cells over 900 cycles with an extremely low capacity degradation rate of 0.017% per cycle. [ABSTRACT FROM AUTHOR]

In an article published in Advanced Functional Materials, Tingting Xu, Hui Wang, Zheng-Long Xu, and their colleagues propose using coplanar heteroacene-cored A-D-A-type molecules as an electron transport layer (ETL) to improve the performance of perovskite solar cells (PSCs). The optimized ETL helps to reduce defects in the perovskite layer, enhances energy alignment at the ETL/perovskite interface, and improves carrier transport efficiency. The resulting indoor light efficiency of the PSCs is reported to be 39.9% under 3000 K LED illumination (1000 lux). [Extracted from the article]

As a promising anode material for Na‐metal batteries, the practical application of Na metal is severely hindered due to the formation of the notorious dendrite and unstable solid‐electrolyte interface (SEI). To address these issues, a direct‐ink writing (DIW) 3D printing technology is proposed to construct an artificial 3D hierarchical porous sodiophilic Nb2CTx/reduced graphene‐oxide (Nb2CTx/rGO) aerogel monolith, which is employed as the matrix of Na metal anode. Benefiting from the homogeneous ion flux and exceptional sodiophilic features, the Nb2CTx nanoflakes embedded within the 3D scaffold regulate the uniform deposition of metallic Na with a stable SEI layer, achieving an ultralong cycle lifespan of 3000 h at 1 mA cm−2 with 1 mAh cm−2 and an impressive Coulombic efficiency of 99.68% over extended lifespan of 7064 h. Further, the in‐depth characterization analysis proves that the formed stable SEI layer consists of an inorganic NaF accumulated in the inner layer and loosely‐bound organic species in the outer layer. Remarkably, when integrated into a Na metal full cell, the reversible capacity reaches 90.22 mAh g−1 after 200 cycles at 100 mA g−1. The work provides a promising strategy to utilize Na metal anodes with long cycle lifespan for next‐generation sodium metal batteries. [ABSTRACT FROM AUTHOR]

Selecting suitable electrode materials for sodium‐ion batteries (SIBs) often relies on the experience gained from lithium‐ion batteries (LIBs), particularly in terms of thermodynamics. However, this approach may fall into a stagnant situation where the development of SIBs consistently lags behind that of LIBs due to the larger ionic radius of Na+. Accordingly, it is crucial to establish a dedicated selection rule specifically tailored for SIB electrodes to overcome this challenge. Herein, a screening method is proposed for SIB materials, where an ideal candidate shall form a stable intermediate transition phase with Na+. This phase acts as an important bridge that can regulate the insertion/extraction of charge carriers. Atomically resolved transmission electron microscopy demonstrates that KCu7S4 can react with Na+ to form a stable intermediate phase (Na3Cu4S4). Na3Cu4S4 can undergo reversible conversion reactions, contribute capacity, stabilize the tunnel structure and enhance the migration/diffusion of Na+. In contrast, Li+ can't form a stable intermediate phase in KCu7S4 during lithiation/delithiation, thus losing the ability to effectively regulate Li+ insertion/extraction. These findings provide valuable insights for the development of suitable electrode materials for SIBs, emphasizing the importance of stable intermediate phases in regulating charge carrier insertion/extraction and improving overall battery performance. [ABSTRACT FROM AUTHOR]

In recent years, hybrid perovskite solar cells (HPSCs) have received considerable research attention due to their impressive photovoltaic performance and low‐temperature solution processing capability. However, there remain challenges related to defect passivation and enhancing the charge carrier dynamics of the perovskites, to further increase the power conversion efficiency of HPSCs. In this work, the use of a novel material, phenylhydrazinium iodide (PHAI), as an additive in MAPbI3 perovskite for defect minimization and enhancement of the charge carrier dynamics of inverted HPSCs is reported. Incorporation of the PHAI in perovskite precursor solution facilitates controlled crystallization, higher carrier lifetime, as well as less recombination. In addition, PHAI additive treated HPSCs exhibit lower density of filled trap states (1010 cm−2) in perovskite grain boundaries, higher charge carrier mobility (≈11 × 10−4 cm2 V−1 s), and enhanced power conversion efficiency (≈18%) that corresponds to a ≈20% improvement in comparison to the pristine devices. [ABSTRACT FROM AUTHOR]

Abstract: This work presents a strategy of combining the concepts of localized surface plasmons (LSPs) and core/shell nanostructure configuration in a single perovskite light‐emitting diode (PeLED) to addresses simultaneously the emission efficiency and stability issues facing current PeLEDs' challenges. Wide bandgap n‐ZnO nanowires and p‐NiO are employed as the carrier injectors, and also the bottom/upper protection layers to construct coaxial core/shell heterostructured CsPbBr3 quantum dots LEDs. Through embedding plasmonic Au nanoparticles into the device and thickness optimization of the MgZnO spacer layer, an emission enhancement ratio of 1.55 is achieved. The best‐performing plasmonic PeLED reaches up a luminance of 10 206 cd m−2, an external quantum efficiency of ≈4.626%, and a current efficiency of 8.736 cd A−1. The underlying mechanisms for electroluminescence enhancement are associated with the increased spontaneous emission rate and improved internal quantum efficiency induced by exciton–LSP coupling. More importantly, the proposed PeLEDs, even without encapsulation, present a substantially improved operation stability against water and oxygen degradation (30‐day storage in air ambient, 85% humidity) compared with any previous reports. It is believed that the experimental results obtained will provide an effective strategy to enhance the performance of PeLEDs, which may push forward the application of such kind of LEDs. [ABSTRACT FROM AUTHOR]

In situ hydrogels have attracted considerable attention in tissue engineering because of their minimal invasiveness and ability to match the irregular tissue defects. However, hydrous physiological environments and the high level of moisture in hydrogels severely hamper binding to the target tissue and easily cause wound infection, thereby limiting the effectiveness in wound care management. Thus, forming an intimate assembly of the hydrogel to the tissue and preventing wound infecting still remains a significant challenge. In this study, inspired by mussel adhesive protein, a biomimetic dopamine-modified ε-poly- l-lysine-polyethylene glycol-based hydrogel (PPD hydrogel) wound dressing is developed in situ using horseradish peroxidase cross-linking. The biomimetic catechol-Lys residue distribution in PPD polymer provides a catechol-Lys cooperation effect, which endows the PPD hydrogels with superior wet tissue adhesion properties. It is demonstrated that the PPD hydrogel can facilely and intimately integrate with biological tissue and exhibits superior capacity of in vivo hemostatic and accelerated wound repair. In addition, the hydrogels exhibit outstanding anti-infection property because of the inherent antibacterial ability of ε-poly- l-lysine. These findings shed new light on the development of mussel-inspired tissue-anchored and antibacterial hydrogel materials serving as wound dressings. [ABSTRACT FROM AUTHOR]