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The unprecedented development of all‐polymer solar cells (all‐PSCs) is hindered by their low short‐circuit current density (Jsc), mainly due to the absence of near‐infrared (NIR) polymer acceptor materials. To tackle this challenge, a molecular design principle is proposed, which involves the regulation of steric hindrance on the fused‐ring backbone to obtain NIR polymer acceptors. Accordingly, three acceptors named PTz‐Ph, PTz‐Me, and PTz‐H are synthesized by substituting the Phenyl, Methyl, and Hydrogen in the beta position of the thiophene unit based on fused‐ring molecules. Different from the necessity of steric hindrance of small molecule acceptors in achieving an outstanding performance, polymer acceptor PTz‐H without steric hindrance‐substitution achieves a record‐high efficiency for the benzotriazole‐based all‐PSCs. Then, introducing PTz‐H into the binary PBDB‐T:PTz‐BO system, the ternary all‐PSC exhibits a splendid efficiency of 18.16%, which has surpassed the efficiencies of most benzo[c][1,2,5]thiadiazole‐based counterparts. In addition, an organic tandem solar cell is successfully fabricated, which exhibits a high efficiency of 17.49%. This work provides an effective and readily accessible design strategy for designing high‐performance NIR polymer acceptors, showing the great potential for future organic photovoltaic applications. [ABSTRACT FROM AUTHOR]

Background: Long sleep duration is a common sleep disorder among elderly people. Dependency increases with increasing age. This study aimed to assess the association between dependency and long sleep duration among elderly people. Methods: This study is a population‐based cross‐sectional study. A total of 1152 participants aged ≥ 60 years were selected from 26 locations in China by a complex multistage sampling design. Data were collected through face‐to‐face interviews. Sleep duration was measured using the Pittsburgh Sleep Quality Index. Dependency was assessed using Minnesota Multiphasic Personality Inventory‐II. Hierarchical multiple linear regression analysis was used to evaluate the efficacy of sleep‐related factors and psychological factors for sleep duration. Analysis of covariance and logistic regression analysis were performed to evaluate the association between the dependency score and sleep duration, and the strength of dependency effect on sleep duration. Results: A total of 1120 participants were valid for the analysis. Among them, 15.8% of participants had a dependency score ≥60 points. The results of hierarchical multiple linear regression analysis showed that sleep duration was positively associated with dependency scores. Analysis of covariance indicated a J‐shaped association between dependency scores and sleep duration. The results of logistic regression analysis showed dependency was significantly associated with long sleep duration, and the odds ratio was 3.52 (95% CI, 1.87–6.63; P < 0.001). Conclusion: Dependency was significantly associated with long sleep duration among elderly people. The results suggested that dependent intervention may be a strategy that needs urgent implementation to reduce long sleep duration among elderly people. [ABSTRACT FROM AUTHOR]

The practical application of lithium (Li) metal battery is impeded by the Li dendrite growth and unstable solid electrolyte interphase (SEI) layer. Herein, an ultra‐stretchable and ionic conducting chemically crosslinked pressure‐sensitive adhesive (cPSA) synthesized via the copolymerization of 2‐ethylhexyl acrylate and acrylic acid with poly(ethyleneglycol)dimethacrylate as crosslinker (short for 70cPSA), is developed as both artificial SEI layer and solid polymer electrolyte (SPE) for stable Li‐metal electrode, enabling all‐solid‐state Li metal batteries with excellent cycling performance. As an artificial SEI layer, the 70cPSA‐modified electrodes exhibit excellent electrochemical performance in Li|70cPSA@Cu half cells and 70cPSA@Li|70cPSA@Li symmetric cells. In full cells with LiFePO4 (LFP) as cathode, the 70cPSA@Li|LFP cell exhibits stable cycling performance over 250 cycles. Utilized as SPE, the all‐solid‐state Li|SPE|LFP cell delivers excellent cycling stability with a capacity retention of 86% over 500 cycles. With high‐voltage LiNi0.8Mn0.1Co0.1O2 (NMC811) as cathode, the Li|SPE|NMC811 cell exhibits a discharge capacity of 124.3 mAh g−1 with a capacity retention of 71% after 200 cycles. The rational design of PSAs and investigation of their dual role for stable and safe Li‐metal batteries may shed a light on adhesive polymers for battery applications. [ABSTRACT FROM AUTHOR]

Comparing with nanometer‐sized Si (nano‐Si), the micrometer‐sized Si (micro‐Si) is more promising for the practical applications due to its low cost and scalable production method. Fabrication of micro‐Si with porous architecture can efficiently alleviate the high mechanical stress and severe mechanical fracture. Till now, it is still a challenge to achieve porous micro‐Si with controlled morphology, such as microsphere, from a cost‐efficient and environmentally friendly approach. Herein, a facile approach on fabricating Si microsphere with porous architecture via a low‐temperature aluminothermic reduction (LTAR) method using the low‐cost fumed silica (FS) as raw material is introduced. After compositing with graphite and then coating with amorphous carbon, the SiFS/graphite@carbon (SiFS/G@C) electrode displays superior reversible capacity (730 mAh g−1 after 100 cycles) and excellent rate capability (729.1 mAh g−1 at 1 A g−1). The electrochemical performance is much better than that of Si‐microparticles/G@C (Mic‐Si/G@C, 368 mAh g−1 at 100 mA g−1 after 100 cycles). These results show the great potential of SiFS/G@C electrode as an alternative high‐performance electrode material for lithium ion batteries. Moreover, the LTAR adopted in the current study significantly reduces the energy consumption for preparation of Si microspheres from low‐cost raw materials. [ABSTRACT FROM AUTHOR]

The vast number of element combinations and the explosive growth of composition space pose significant challenges to the development of high-entropy alloys (HEAs). Here, we propose a procedural research method aimed at accelerating the discovery of efficient electrocatalysts for oxygen reduction reaction (ORR) based on Pt-based quinary HEAs. The method begins with an element library provided by a large language model (LLM), combined with microscale precursor printing and pulse high-temperature synthesis techniques to prepare multi-element combination HEA array in one step. Through high-throughput measurement using scanning electrochemical cell microscopy (SECCM), precise identification of highly active HEA element combinations and exploration of composition space for a specific combination are achieved. Advantageous element combinations are further validated in practical electrocatalytic evaluations. The contributions of individual element sites and the synergistic effects among elements of such HEAs in enhancing reaction activity are elucidated via density functional theory (DFT) calculations. This method integrates high-throughput experiments, practical catalyst validation, and DFT calculations, providing a new pathway for accelerating the discovery of efficient multi-element materials in the field of energy catalysis., (© 2024 Wiley‐VCH GmbH.)

Silicon (Si) is a promising candidate for high-capacity anode materials owing to its high theoretical capacity (3579 mAh g -1 ), low working voltage, and wide natural abundance, although its huge volume variation during charge/discharge processes always results in a short cycling life. Polymer binders play a vital role in improving the cycling performance of Si-based anodes, although traditional polyvinylidene difluoride cannot fulfil the requirements owing to its weak van der Waals forces with the Si surface. Recently, polymer binders constructed by dynamic bonds have been developed, which are reported to allow high-energy-density electrodes with improved electrochemical performance. With dynamic bonds including hydrogen bonding, ionic bonding, and host-guest interactions, these polymer binders possess self-healing capabilities and enhanced mechanical performance, achieving a tremendous advance in addressing the capacity fading of Si-based anodes. In this review, we will summarize the research progress of polymer binders constructed with dynamic bonds, and the challenges for their real applications in advanced Li-ion batteries will also be discussed., (© 2019 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)