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Safe and high‐performance secondary batteries using for all‐climate conditions with different temperatures are highly required. Here, we develop a three‐dimensional ball cactus‐like MgV2O4 as cathode material for magnesium‐ion (Mg‐ion) batteries. After cycling 300 times, the capacity maintains 111.7 mAh g−1, while Coulombic efficiency stabilizes at about 100 %. Under temperatures of 45 °C and −5 °C, the capacities remain stable after 200 cycles. After three rounds of rate‐performance tests, the capacity keeps quite stable. It is ascribed to the ball cactus‐like morphology buffers the volumetric change during Mg2+ insertion/extraction, and provides sufficient pathways for ion diffusion, which has been verified by constant‐current intermittent titration technology. It is believed that the good performance enables the Mg‐ion batteries to have a all‐climate capability. [ABSTRACT FROM AUTHOR]

During the slab sizing press (SP) process, the pressing force corresponds to the slab profile, which guides the production schedule design and the final profile control. To accomplish the prediction of pressing force for SP, an improved ensemble method based on chaotic Harris hawks optimizer (CHHO) and stacking is proposed. A mechanistic knowledge is introduced for feature selection that enhances the rationality of input features. Subsequently, 11 machine learning models are compared and 5 of them are selected as candidate learners for the stacking method. Based on the candidates learners, 8 stacking strategies are constructed, which the stacked model with extratree regressor, gradient boosted decision trees, and kernel ridge regression (KRR) as base‐learners and KRR as meta‐learner performs the best. The R2, MAE, mean square error, mean squared log error, and mean absolute percentage error for the test dataset are 0.9912, 0.0856, 0.0167, 0.0005, and 2.00%, respectively, and 95% of the prediction errors are less than 0.15 MN. Then, sensitivity analysis and predictive analysis based on Shapley Additive Explanations are performed to demonstrate the good alignment of the proposed model with physical reality. Furthermore, to cope with the complexity and uncertainty of the production process, the proposed CHHO‐stacking model and the kernel density estimation method are integrated to model the prediction interval. [ABSTRACT FROM AUTHOR]

Anhui Provincial Engineering Laboratory for Engineering appropriate cathode materials is significant for the development of high‐performance aluminum‐ion (Al‐ion) batteries. Here, a pyramidal metal–organic frameworks (MOFs)‐derived FeP@CoP composite was developed as cathode, which exhibits good stability and high capacity. FeP@CoP cathode maintains a high capacity of 168 mAh g−1 after 200 cycles, and displays a stable rate‐performance at both room and low temperatures of −10 °C. After three rounds of rate‐performance cycling, the FeP@CoP composite recovers 178.2 mAh g−1 at 0.3 A g−1. Moreover, density functional theory (DFT) calculations verify improved electron‐transfer kinetics with narrowed band gap and enhanced density of states. These findings inspire a broad set of studies on MOFs‐derived composites for high‐performance secondary batteries. [ABSTRACT FROM AUTHOR]

A foldable battery with high flexibility provides great potential in various wearable electronic devices for health and fitness tracking, chronic disease management, performance monitoring, navigation tracking, and portable gears for soldiers. We report a highly flexible, self‐healing Zn‐ion battery with a free‐standing cathode that is composed of a 3D gear‐like NH4V4O10@C composite on carbon paper. The battery retained a capacity of up to 102.4 mAh g−1 even after being folded 60 times with a high angle of 180°. An aqueous hydrogel consisting polyvinyl alcohol, glycerin and Zn(CF3SO3)2 was used as electrolyte, which showed as high as 580 % tensile strain under a loading weight of 78 N. The battery exhibited a better capacity retention of over 100 mAh g−1 and Coulombic efficiency of over 99.8 % after cutting and twisting to 90°, thereby indicating a great self‐healing performance. The gear‐like geometry greatly improved the volume accommodation due to the increased interval space between the blades and the outward configuration. Meanwhile the Zn2+ ionic conductivity was improved by rapid re‐binding of many existing hydroxy groups from the electrolyte and the enhanced contact surface area and diffusion route from the cathode material. The highly flexible, safe aqueous Zn‐ion battery opens a practical way to power various carry‐on electronics under mechanical agitation. [ABSTRACT FROM AUTHOR]

The shuttling behavior and slow conversion kinetics of the intermediate lithium polysulfides are the severe obstacles for the application of lithium‐sulfur (Li‐S) batteries over a wide temperature range. Here, an engineered lamellar yolk–shell structure of In2O3@void@carbon for the Li‐S battery cathode is developed for the first time to construct a powerful barrier that effectively inhibits the shuttling of polysulfides. On the basis of the unique nanochannel‐containing morphology, the continuous kinetic transformation of sulfur and polysulfides is confined in a stable framework, which is demonstrated by using X‐ray nanotomography. The constructed Li‐S battery exhibits a high cycling capability over 1000 cycles at 1.0 C with a capacity decay rate as low as 0.038% per cycle, good rate performance, and temperature tolerance at −10, 25, and 50 °C. A nondestructive in situ monitoring method of the interfacial reaction resistance in different cycling stages is proposed, which provides a new analysis perspective for the development of emerging electrochemical energy‐storage systems. [ABSTRACT FROM AUTHOR]

Self‐healing secondary batteries have attracted great attention for constructing stable energy‐storage systems. Herein, a novel self‐healing rechargeable magnesium battery cathode is developed using self‐healing microcapsules in a vanadium pentoxide microflower‐based cathode. The microcapsules are prepared through a microfluidic approach. The core of the microcapsule contains a conductive hydrogel and carbon nanospheres, and the shell composes of a UV‐curved polymer. When the self‐healing Mg battery cathode cracks, the microcapsules break and release the core into the cracks, rebuilding the pathways for the electron transport and enabling a stable electrochemical performance. The presented cathode displays a good capacity of 105 mAh g−1 after 500 cycles at 100 mA g−1 and it delivers a stable capacity of 98.3 mAh g−1 after long‐term cycling 1000 times at 200 mA g−1. A recoverable rate‐performance and a good temperature tolerance are also achieved. It is expected that the general preparation approach of the self‐healing microcapsules and the long‐term stable Mg battery will find broad applications for developing many emerging energy‐storage systems. [ABSTRACT FROM AUTHOR]

Silicon is regarded as one of the most important high‐capacity materials and has been added to some commercial anodes to increase the specific energy of lithium‐ion batteries (LIBs). However, the large volume change of Si during cycling leads to cracking, continuous accumulation of solid electrolyte interphase (SEI), and electric disconnection, posing a major challenge to practical applications. In this review, the latest progress on practical Si anodes and the scalable fabrication technologies, including synthesis of nanostructured Si, Si/C, SiOx composites, and binders is proposed. At last, a perspective of future studies on nano‐Si‐based anodes is suggested and, from a practical viewpoint, the rational design of high‐capacity Si anodes for better LIBs to narrow the gap between nanostructural design and practical applications is discussed. [ABSTRACT FROM AUTHOR]

Self‐healing and flexibility are significant for many emerging applications of secondary batteries, which have attracted broad attention. Herein, a self‐healing flexible quasi‐solid Zn‐ion battery composing of flexible all‐in‐one cathode (VS2 nanosheets growing on carbon cloth) and anode (electrochemically deposited Zn nanowires), and a self‐healing hydrogel electrolyte, is presented. The free‐standing all‐in‐one electrodes enable a high capacity and robust structure during flexible transformation of the battery, and the hydrogel electrolyte possesses a good self‐healing performance. The presented battery remains as a high retention potential even after healing from being cut into six pieces. When bending at 60°, 90°, and 180°, the battery capacities remain 124, 125, and 114 mAh g−1, respectively, cycling at a current density of 50 mA g−1. Moreover, after cutting and healing twice, the battery still delivers a stable capacity, indicating a potential use of self‐healing and wearable electronics. [ABSTRACT FROM AUTHOR]

Hollow nanomaterials have attracted broad attention due to their geometric configuration with some special properties such as fast ion diffusion, and accommodating structural transformation. However, conventional approaches for preparing hollow nanostructure commonly need an additional template removal process, which is time‐consuming and may require some corrosive chemicals. Herein, a general template‐induced sulfuration method is presented which is applicable for preparing a broad set of hollow sulfides. Sulfur particles are synthesized, which are then used as both template and sulfurizing reagent. During the heating, the template is removed along with the sublimation of sulfur, meanwhile the sulfur vapors sulfurize the coated precursor, finally forming a hollow sulfide nanostructure. As a demonstrating case study, a hollow NiS2 nanostructure is prepared through the presented approach which is confirmed extendable for many other sulfides such as CoS2, Bi2S3, and Cu2S. Furthermore, the hollow NiS2 exhibits bifunctional properties using as Al‐ion battery cathode and Li‐ion battery anode with good electrochemical performance, such as a 1000‐cycles stable capacity at high current density of 5 A g−1, stable temperature‐endurable property, and well‐recoverable rate performance. [ABSTRACT FROM AUTHOR]

Magnesium batteries have been considered promising candidates for next‐generation energy storage systems owing to their high energy density, good safety without dendrite formation, and low cost of magnesium resources. However, high‐performance cathodes with stable capacity, good conductivity, and fast ions transport are needed, since many conventional cathodes possess a low performance and poor preparation controllability. Herein, a liquid‐driven coaxial flow focusing (LDCFF) approach for preparing a novel microcapsule system with controllable size, high loading, and stable magnesium‐storage performance is presented. Taking the MoS2‐infilled microcapsule as a case study, the magnesium battery cathode based on the microcapsules displays a capacity of 100 mAh g−1 after 100 cycles. High capacity retention is achieved at both low and high temperatures of −10, ‒5, and 45 °C, and a stable rate‐performance is also obtained. The influences of the liquid flow rates on the size and shell thickness of the microcapsules are investigated; and electron and ion diffusion properties are also studied by first‐principle calculations. The presented LDCFF method is quite general, and the high performance of the microcapsules enables them to find broad applications for making emerging energy‐storage materials and secondary battery systems. [ABSTRACT FROM AUTHOR]

Carbon dioxide has attracted considerable attention owing to its physics and abundant polymorphs. Despite decades of extensive experiments and theoretical simulations, the structure and properties of carbon dioxide under extreme pressures and temperatures are yet to be properly understood. Particularly, the intermediate phase IV of solid carbon dioxide, which separates the molecular phases at low pressures from the non‐molecular phases at high pressures, has not been fully investigated, and its structure remains controversial. Here, based on the second‐order Møller‐Plesset perturbation (MP2) theory and the embedded fragment method, we study the crystal structure, equation of state, and Raman spectra of solid carbon dioxide phase IV at high pressures and temperatures. We demonstrate that the solid carbon dioxide phase IV is a molecular structure that remains in a molecular state rather than the bent state shown in other literature works, which is consistent with the experimental work by Datchi et al and denies the observed results by Park et al. The proposed work is of great significance in determining the structure of the high‐pressure phases of carbon dioxide and further exploring the new phase of molecular crystals. [ABSTRACT FROM AUTHOR]

Alcohol has a potential health risk to human health, so it is important to realise the rapid detection of alcohols. Based on this, the nano Na2Mg(CO3)2 was prepared by a simple hydrothermal method to establish a cataluminescence (CTL) gas sensor for alcohols. The Na2Mg(CO3)2with highly purified quality was characterised by scanning electron microscope, energy dispersive spectroscopy and the powder X‐ray diffraction. The results show that the nano Na2Mg(CO3)2 is a peony‐like substance with a large surface area, which will be beneficial to produce ultra‐weak chemiluminescence reaction between the detector and the material. The peony‐like Na2Mg(CO3)2 has good CTL response to alcohols (methanol, ethanol, n‐propanol and n‐butanol), showing high selectivity. The response time of Na2Mg(CO3)2 for four alcohols is between 1 and 2 s, which indicate that the material has the advantage of rapid response. The limit of detection of four alcohols defined as 3 N/S is about 7.91, 4.75, 6.69 and 8.10 mg/l, respectively. The optimum reaction conditions of the gas sensor based on nano Na2Mg(CO3)2 are mild and this nanomaterial can be used for alcohol detection. [ABSTRACT FROM AUTHOR]

Microencapsulated materials are receiving broad attention for applications as diverse as energy storage and conversion, biomedicine, self‐healing materials, and electronics. Here, a general microfluidic approach is presented to prepare phase‐change material‐infilled microcapsules with unique thermal and mechanical properties. Aqueous sodium acetate solutions are encapsulated by an acrylate‐based shell via a microfluidic method. To understand and optimize microcapsule formation, flow behavior during the encapsulation is numerically simulated. When the microcapsules are embedded in an acrylate matrix (same composition as the shell wall material), the microcapsules exhibit a significant 46.6 ºC difference between the crystallization and melting temperatures as determined by differential scanning calorimetry at a rate of 10 ºC per min. Variable temperature dynamic mechanical analysis over the range of 50 to ‐90 ºC reveals up to a 50% change in the composite's elastic modulus at a given temperature, depending on if the sample is being cooled or heated, due to significant undercooling of the core material crystallization as shown by X‐ray diffraction. [ABSTRACT FROM AUTHOR]

Lithium (Li) metal anodes are demanded by high‐energy Li batteries because Li has the highest capacity and low electrode potential. However, Li metal anodes usually show poor cyclability and unsafe deposition at anode/separator interfaces, which may increase the risk of short circuits. In this work, we fabricate a sandwiched structure of reduced graphene oxides (rGO) with silicon (Si) quantum dots (QDs) as the inducing agents between rGO layers. Because of the lithiophilicity of Si QDs, Li growth is favorably guided away from the unsafe anode/separator interface towards the interlayer positions, significantly improving the cyclability and safety of the Si‐QDs‐sandwiched rGO anode. The uniformly‐distributed Si QDs and layered electrode structure can regulate Li plating/stripping to avoid the superficial Li growth and reduce the accumulation of solid electrolyte interphase. The growth‐guiding strategy using the sandwiched structure provides a new approach to fabricating high energy Li‐based battery anodes. [ABSTRACT FROM AUTHOR]

Large volume expansion and structural breaking have been severe issues for emerging high‐performance secondary battery anodes. Herein, a novel microcapsule anode filled with tin (Sn) nanoflowers is presented, which is prepared through in situ interface polymerization of an oil‐in‐water emulsion system. The carbon shell of the microcapsules reduces the pulverization of the encapsulated Sn, and the voids inside the capsules provide efficient spaces for the volume change of Sn during lithiation–delithiation. The Sn‐filled microcapsules exhibit a high rate performance with a capacity decay rate as low as 0.38%, even after three rounds of repeated tests, and a stable capacity of 800 mAh g−1 after 200 cycles at 380 mA g−1. In addition, the electron transfer kinetics and Li‐ion diffusion are investigated, which indicate that the microcapsule system enables a good environment for both electron and ion transfer. [ABSTRACT FROM AUTHOR]

Current high‐energy‐density secondary battery electrodes have several issues, in major part due to mechanical instabilities. Herein, a novel, mechanically robust anode is presented, which consists of a leaf‐shaped architecture with high lithium‐storage performance. As a demonstrative example, a leaf‐shaped tin dioxide (SnO2) anode is prepared through a templated layer‐by‐layer approach. The robust mechanical properties of the SnO2 anode are demonstrated through density functional theory (DFT) in which principle stress caused by lithiation is calculated. Real‐time lithiation is observed using in situ transmission electron microscopy (TEM) technology. The presented anode shows a stable capacity of 760 mAh g−1 after 200 cycles at 0.2 C, and a high capacity retention of 99% is achieved after three rounds of measurements. [ABSTRACT FROM AUTHOR]

High energy density Li−S battery has attracted wide attention because of its promising application in long driving‐range electric vehicles. However, the shuttle effect of polysulfides, electrical insulation and volume‐change of sulfur, remain great challenges. Herein, inspired from a natural mimosa pudica structure, we present a novel nanocomposite which consists of a mimosa pudica‐structured carbon matrix coating with sulfur. The biomimetic configuration is able to structurally‐respond to the volume‐change of sulfur during charge/discharge; and the carbon matrix provides a good conductivity for rapid electron transfer. The carbon/sulfur composite‐based Li−S batteries exhibit a good electrochemical performance including a stable capacity after 1000 cycles, along with a Coulombic efficiency as high as 99.6 %, and an excellent rate‐performance even after three rounds of measurements. In addition, the density function theory modeling is investigated, which confirms the adsorption effect of carbon towards the polysulfides including Li2S4, Li2S6, and Li2S8, enabling a long‐term cycling stability. [ABSTRACT FROM AUTHOR]

This article studies the morphological and mechanical features of multinuclear and mononuclear SW480 colon cancer cells by atomic force microscopy to understand their drug-resistance. The SW480 cells were incubated with the fullerenol concentrations of 1 mg/ml and 2 mg/ml. Morphological and mechanical features including the height, length, width, roughness, adhesion force and Young's modulus of three multinuclear cell groups and three mononuclear cell groups were imaged and analyzed. It was observed that the features of multinuclear cancer cells and mononuclear cancer cells were significantly different after the treatment with fullerenol. The experiment results indicated that the mononuclear SW480 cells were more sensitive to fullerenol than the multinuclear SW480 cells, and the multinuclear SW480 cells exhibited a stronger drug-resistance than the mononuclear SW480 cells. This work provides a guideline for the treatments of multinuclear and mononuclear cancer cells with drugs. [ABSTRACT FROM AUTHOR]

FeF2 is considered a promising conversion compound for the positive electrode in lithium-ion batteries due to its high thermodynamic reduction potential (2.66 V vs Li/Li+) and high theoretical specific capacity (571 mA h g−1). However, the sluggish reaction kinetics and rapid capacity decay caused by side reactions during cycling limit its practical application. Here, the fabrication of Ni-supported 3D Al2O3-coated FeF2 electrodes is presented, and it is shown that these structured electrodes significantly overcome these limitations. The electrodes are prepared by iron electrodeposition on a Ni support, followed by a facile fluorination process and Al2O3 coating by atomic layer deposition. The 3D FeF2 electrode delivers an initial discharge capacity of 380 mA h g−1 at a current density of 200 mA g−1 at room temperature. The 3D scaffold improves the reaction kinetics and enables a high specific capacity by providing an efficient electron pathway to the insulating FeF2 and short Li diffusion lengths. The Al2O3 coating significantly improves the cycle life, probably by preventing side reactions through limiting direct electrode-electrolyte contact. The fabrication method presented here can also be applied for synthesis of other metal fluoride materials on different 3D conductive templates. [ABSTRACT FROM AUTHOR]

There have been significant recent developments in the growth of single‐crystal gallium nitride (GaN) on unconventional templates for large‐area blue or green light‐emitting diodes (LEDs) which, together with layer transfer onto foreign substrates, can enable flexible and stretchable lighting applications. Here, the heteroepitaxial growth of GaN on amorphous and single‐crystal substrates employing various interlayers and nucleation layers is reviewed, as well as the use of weak interfaces for layer‐transfer onto foreign substrates. Recent progress in low‐temperature GaN‐based red–green–blue (RGB) LEDs on glass substrates, which has exhibited a calculated efficiency of 11% compared with that from commertial LEDs, is discussed. Layer‐transfer techniques with various interlayers are also discussed. These heteroepitaxial GaN growth and layer‐transfer technologies are expected to lead to new lighting and display devices with high efficiency and full‐color tunability, which are suitable for large‐area, stretchable display and lighting applications. [ABSTRACT FROM AUTHOR]

We model histories between two cohorts of urban Chinese couples (N = 1,191) of a rarely studied living arrangement—coresidence with the wife's parents—using a dynamic life history analysis in contrast to previous cross-sectional studies of coresidence. We examine patterns of entry into and exit from coresidence with the wife's parents, comparing the predictive power of modernization theory to the effect of demographic change and the resources and needs of each generation. Given China's well-known patrilineal family system, we find a surprisingly high number of couples ever residing nonnormatively, and significant differences between cohorts in what determines the pattern of coresidence. Resources and needs that reflect conscious choices to coreside most strongly influence nonnormative coresidence. Its importance may increase as the children of the One-Child Family Policy grow up and marry. [ABSTRACT FROM AUTHOR]

Chemically and mechanically robust sulfur (S) cathodes are highly significant for high‐performance lithium‐sulfur (Li‐S) batteries. Herein, a novel 3D hydrogel@S composite as binder‐free high‐performance cathode is presented, which consists of a 3D conductive hydrogel polyaniline (PAN) scaffold coated with dense S particles. The 3D PAN@S composite exhibits polysulfides‐adsorptive performance, suitable structure for accommodating the volume change of S upon lithiation, and improved overall conductivity of the electrode. After cycling for 100 times at 0.2 C, the binder‐free 3D PAN@S composite shows a capacity of 816 mAh g−1, along with a Coulombic efficiency as high as 99.9%. A good electrochemical performance is also achieved when cycling at a high temperature of 50 °C. In addition, the adsorptive effect of PAN towards polysulfides is demonstrated through density functional theory calculations on the adsorption energies. [ABSTRACT FROM AUTHOR]

Lithium metal anodes suffer from serious safety issues and rapid capacity fade because of nonideal plating/stripping behaviors. Lithium nucleation on undesired positions usually results from nonuniform multiphysical field distributions and the dynamically changing interface thermodynamics. In this study, a sandwich composite anode consisting of gold nanoparticles pillared reduced graphene oxide (rGO) is designed. Because gold nanoparticles preferentially induce lithium nucleation, the typically uncontrolled lithium deposition process becomes a highly nucleation‐guided process. Because the sandwich structure of the Au‐pillared rGO provides a stable anode morphology with cycling and stabilizes the solid electrolyte interface layer, the Au‐pillared rGO delivers a high Coulombic efficiency of up to 98% for at least 200 cycles for 1600 h. Using this pillared structure, an interlayer plating process is revealed in rGO‐sandwiched anodes, which differ from either conventional metallic anodes or intercalation anodes. The Au‐pillared design bridges the gap between metal and intercalation anodes, and provides a novel strategy to improve the efficiencies and cyclability of lithium anodes. An interlayer plating mechanism for metallic lithium anodes is revealed in a sandwich structure with gold nanoparticles pillared reduced graphene oxide. The layered composite anode is able to guide lithium plating and realize uniform through‐plane expansion and contraction, which stabilizes the solid electrolyte interphase and enhances the cyclability of metallic lithium anodes. [ABSTRACT FROM AUTHOR]