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As a candidate for a new generation of inexpensive and high‐performance energy storage systems, lithium–sulfur (Li–S) batteries have attracted widespread research. However, the development and application of Li–S batteries are limited by severe polysulfide dissolution and slow reaction kinetics. Herein, a type of ordered mesoporous P‐TiO2−x microsphere with a waxberry‐like shape as the sulfur host material for Li–S batteries is put forward, which combines the radially arranged mesoporous structure with oxygen defects in the mesoporous framework. In addition, the introduction of phosphorus impurities greatly improves the conductivity of the sulfur electrode, enhances electron mobility, and promotes the interaction between the sulfur species and P‐TiO2−x microspheres. Finally, S/P‐TiO2−x cathodes have achieved a high capacity of 1174.9 mAh g−1 at 0.2C and stable cycling (the average capacity attenuation is only 0.086% per cycle at 1C after 600 cycles).

Li-S battery, new type catalyst, dual-defect MOF, multiple conversion reaction, polysulfides Keywords: Li-S battery; new type catalyst; dual-defect MOF; multiple conversion reaction; polysulfides EN Li-S battery new type catalyst dual-defect MOF multiple conversion reaction polysulfides 1 1 1 10/12/23 20231016 NES 231016 B The sluggish sulfur redox kinetics b and shuttle effect of lithium polysulfides are recognized as the main obstacles to the practical applications of lithium-sulfur (Li-S) batteries. In their Research Article (e202306901), Dan Luo, Zhongwei Chen et al. report a novel dual-defect metal-organic framework (MOF) as a new catalyst type to achieve synergistic catalysis for the multi-step conversion reaction of lithium polysulfides. [Extracted from the article]

In their Research Article (e202306901), Dan Luo, Zhongwei Chen et al. report a novel dual-defect metal-organic framework (MOF) as a new catalyst type to achieve synergistic catalysis for the multi-step conversion reaction of lithium polysulfides. Back Cover: Accelerated Multi-step Sulfur Redox Reactions in Lithium-Sulfur Batteries Enabled by Dual Defects in Metal-Organic Framework-based Catalysts (Angew. Keywords: Li-S battery; new type catalyst; dual-defect MOF; multiple conversion reaction; polysulfides EN Li-S battery new type catalyst dual-defect MOF multiple conversion reaction polysulfides 1 1 1 10/12/23 20231016 NES 231016 B The sluggish sulfur redox kinetics b and shuttle effect of lithium polysulfides are recognized as the main obstacles to the practical applications of lithium-sulfur (Li-S) batteries. [Extracted from the article]

The sluggish sulfur redox kinetics and shuttle effect of lithium polysulfides (LiPSs) are recognized as the main obstacles to the practical applications of the lithium‐sulfur (Li−S) batteries. Accelerated conversion by catalysis can mitigate these issues, leading to enhanced Li−S performance. However, a catalyst with single active site cannot simultaneously accelerate multiple LiPSs conversion. Herein, we developed a novel dual‐defect (missing linker and missing cluster defects) metal–organic framework (MOF) as a new type of catalyst to achieve synergistic catalysis for the multi‐step conversion reaction of LiPSs. Electrochemical tests and first‐principle density functional theory (DFT) calculations revealed that different defects can realize targeted acceleration of stepwise reaction kinetics for LiPSs. Specifically, the missing linker defects can selectively accelerate the conversion of S8→Li2S4, while the missing cluster defects can catalyze the reaction of Li2S4→Li2S, so as to effectively inhibit the shuttle effect. Hence, the Li−S battery with an electrolyte to sulfur (E/S) ratio of 8.9 mL g−1 delivers a capacity of 1087 mAh g−1 at 0.2 C after 100 cycles. Even at high sulfur loading of 12.9 mg cm−2 and E/S=3.9 mL g−1, an areal capacity of 10.4 mAh cm−2 for 45 cycles can still be obtained. [ABSTRACT FROM AUTHOR]

Electric detection of spin currents is critical for integrating spintronic devices into charge-based semiconductor chips and systems. The magnetogyrotropic photogalvanic effect (MPGE) converts spin current into charge current through spin–orbit coupling in the presence of an in-plane magnetic field. A giant MPGE photocurrent implies either a large spin current or high spin-to-charge conversion efficiency, whichever is important for future spintronic devices. In this Letter, we report on the MPGE photocurrents excited by linearly polarized near-infrared radiation in a GaAs/Al0.3Ga0.7As heterostructure, which are increased by up to five times by an additional visible light with adjustable power. We present a theoretical model and suggest that the optical manipulation of the linear MPGE photocurrent is primarily attributed to the spin current tuned by the momentum relaxation time and spin splittings. [ABSTRACT FROM AUTHOR]

Physical activity recognition is a field that infers human activities used in machine learning techniques through wearable devices and embedded inertial sensors of smartphones. It has gained much research significance and promising prospects in the fields of medical rehabilitation and fitness management. Generally, datasets with different wearable sensors and activity labels are used to train machine learning models, and most research has achieved satisfactory performance for these datasets. However, most of the methods are incapable of recognizing the complex physical activity of free living. To address the issue, we propose a cascade classifier structure for sensor-based physical activity recognition from a multi-dimensional perspective, with two types of labels that work together to represent an exact type of activity. This approach employed the cascade classifier structure based on a multi-label system (Cascade Classifier on Multi-label, CCM). The labels reflecting the activity intensity would be classified first. Then, the data flow is divided into the corresponding activity type classifier according to the output of the pre-layer prediction. The dataset of 110 participants has been collected for the experiment on PA recognition. Compared with the typical machine learning algorithms of Random Forest (RF), Sequential Minimal Optimization (SMO) and K Nearest Neighbors (KNN), the proposed method greatly improves the overall recognition accuracy of ten physical activities. The results show that the RF-CCM classifier has achieved 93.94% higher accuracy than the 87.93% obtained from the non-CCM system, which could obtain better generalization performance. The comparison results reveal that the novel CCM system proposed is more effective and stable in physical activity recognition than the conventional classification methods. [ABSTRACT FROM AUTHOR]

As a candidate for a new generation of inexpensive and high‐performance energy storage systems, lithium–sulfur (Li–S) batteries have attracted widespread research. However, the development and application of Li–S batteries are limited by severe polysulfide dissolution and slow reaction kinetics. Herein, a type of ordered mesoporous P‐TiO2−x microsphere with a waxberry‐like shape as the sulfur host material for Li–S batteries is put forward, which combines the radially arranged mesoporous structure with oxygen defects in the mesoporous framework. In addition, the introduction of phosphorus impurities greatly improves the conductivity of the sulfur electrode, enhances electron mobility, and promotes the interaction between the sulfur species and P‐TiO2−x microspheres. Finally, S/P‐TiO2−x cathodes have achieved a high capacity of 1174.9 mAh g−1 at 0.2C and stable cycling (the average capacity attenuation is only 0.086% per cycle at 1C after 600 cycles). [ABSTRACT FROM AUTHOR]

Lithium–sulfur (Li–S) batteries present a promising solution to high‐energy and low‐cost energy storage. However, the conversion‐type redox mechanism determines the poor fulfillment of battery chemistry in terms of reversibility and kinetics. Herein, a flower‐like graphene microassembly decorated with finely‐dispersed Ni2Co nanoalloy (Ni2Co@rGO) is developed as advanced host matrix for Li–S batteries. Combining computational, physicochemical, and electrochemical studies, Ni2Co nanoalloys are unveiled synergizing strong adsorbability against polysulfide shuttling and excellent catalytic activity for sulfur conversions. Meanwhile, the sophisticated architecture renders facile electron/ion transport and highly‐exposed active interfaces. These virtues collaboratively contribute to fast and durable sulfur electrochemistry with a minimum capacity degradation of 0.034% per cycle over 500 cycles and a rate capability up to 5 C. Besides, the implementation of Ni2Co@rGO as the anode matrix tames the Li redox behavior benefiting from the enhanced lithiophilicity and reduced local current density. As such, the full cell configuration pairing S‐Ni2Co@rGO cathode and Li‐Ni2Co@rGO anode realizes a favorable areal capacity of 4.53 mAh cm−2 under high sulfur loading (4.0 mg cm−2) and limited electrolyte (E/S = 6.0 mL g−1). This work offers an elaborate bi‐service matrix engineering to simultaneously improve the conversion reversibility and kinetics for superior Li–S batteries. [ABSTRACT FROM AUTHOR]

Copyright of Application Research of Computers / Jisuanji Yingyong Yanjiu is the property of Application Research of Computers Edition and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Application Research of Computers / Jisuanji Yingyong Yanjiu is the property of Application Research of Computers Edition and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of China Medical University is the property of Journal of China Medical University Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of China Medical University is the property of Journal of China Medical University Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)