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Abstract: Extensive effort is being made into cathode materials for sodium‐ion battery to address several fatal issues, which restrict their future application in practical sodium‐ion full cell system, such as their unsatisfactory initial Coulombic efficiency, inherent deficiency of cyclable sodium content, and poor industrial feasibility. A novel air‐stable O3‐type Na[Li0.05Mn0.50Ni0.30Cu0.10Mg0.05]O2 is synthesized by a coprecipitation method suitable for mass production followed by high‐temperature annealing. The microscale secondary particle, consisting of numerous primary nanocrystals, can efficiently facilitate sodium‐ion transport due to the short diffusion distance, and this cathode material also has inherent advantages for practical application because of its superior physical properties. It exhibits a reversible capacity of 172 mA h g−1 at 0.1 C and remarkable capacity retention of 70.4% after 1000 cycles at 20 C. More importantly, it offers good compatibility with pristine hard carbon as anode in the sodium‐ion full cell system, delivering a high energy density of up to 215 W h kg−1 at 0.1 C and good rate performance. Owing to the high industrial feasibility of the synthesis process, good compatibility with pristine hard carbon anode, and excellent electrochemical performance, it can be considered as a promising active material to promote progress toward sodium‐ion battery commercialization. [ABSTRACT FROM AUTHOR]

Abstract: Sodium‐ion batteries (SIBs) have been considered as the most promising candidate for large‐scale energy storage system owing to the economic efficiency resulting from abundant sodium resources, superior safety, and similar chemical properties to the commercial lithium‐ion battery. Despite the long period of academic research, how to realize sodium‐ion battery commercialization for market applications is still a great challenge. Thus, from the perspective of future practical application, this review will identify the factors that are restricting commercialization, and evaluate the existing active materials and sodium‐ion‐based full‐cell system. The design and development trends that are needed for SIBs to meet the requirements of practical applications in large‐scale energy storage will also be discussed in detail. [ABSTRACT FROM AUTHOR]

The non-aqueous lithium oxygen battery has been considered as one of the most promising energy storage systems owing to its potentially high energy density, exceeding that of any other existing storage system for storing sustainable and clean energy. The success of Li-O2 batteries could efficiently reduce greenhouse gas emissions and the consumption of non-renewable fossil fuels. How to achieve high round-trip efficiency, high capacity, and satisfactory cycling performance, however, is still a great challenge for the lithium oxygen battery. Thus, this report will point out what factors will affect the electrochemical performance and will aim to describe how to increase the electrochemical performance by air electrode optimization. Based on recent achievements, several approaches to solving this problem, such as synthesizing electrocatalysts with high catalytic activity and designing appropriate air electrode structures, are described in details. Also, recent progress associated with novel air electrode designs and understanding the reaction process is discussed. [ABSTRACT FROM AUTHOR]

A hybrid gel–solid-state polymer electrolyte has been used as the separator and an electrolyte for lithium oxygen batteries. It can not only avoid electrolyte evaporation but also protect the lithium metal anode during reactions over long-term cycling. Due to its high ionic conductivity and low activation energy, excellent cycling performance is demonstrated, in which the terminal voltage is higher than 2.2 V after 140 cycles at 0.4 mA cm−2, with a capacity of 1000 mA h g(composite)−1. [ABSTRACT FROM AUTHOR]

The development of potassium‐ion batteries (KIBs) relies on the exploration of stable layer‐structured oxide cathode materials and a comprehensive understanding of ion storage and diffusion behaviors. A multiphase riveting‐structured O3/P2/P3‐Na0.9[Ni0.3Mn0.55Cu0.1Ti0.05]O2 (Tri‐NMCT) is employed as cathode material for KIBs. It demonstrates an initial discharge specific capacity of 108 mA g−1 at current density of 15 mA g−1 in the voltage range of 1.5–4 V. Excellent cyclic stability is exhibited as well with a high 83% capacity retention after 600 cycles at a higher current density of 300 mA g−1. Based on the in‐situ XRD, it reveals that the P2 phase offers a more stable triangular prism site compared to the O3 phase. This stability inhibits the undesired phase transition from P3 to O3 during discharge, thereby ensuring the long‐term cyclic performance. Furthermore, Density of state (DOS) calculations and migration barrier analyses indicate a preferential migration of K+ ions to the P2 phase due to the lower Fermi level. This observation elucidates the structural preservation of the P3 phase during K+ embedding. Overall, this work sheds light on Tri‐NMCT as a promising cathode material for advanced KIBs. [ABSTRACT FROM AUTHOR]

Potassium metal batteries (PMBs) are regarded as viable candidates for future electrochemical energy storage devices with potential high energy density and low cost. However, uncontrollable potassium dendrite growth and huge volume expansion severely inhibit the practical application of PMBs. Herein, inspired by the structure and functionalities of tree bark, an antimony (Sb) nano‐clusters decorated N‐doped interconnected carbon nanospheres/potassium composite electrode with biomimetic fast ionic channels is developed to realize the dendrite‐free potassium metal batteries. The composite electrode provides abundant nucleation sites and interconnected ion transport channels, facilitating rapid ion transport kinetics and highly reversible potassium plating/stripping behaviors. Consequently, the assembled symmetric cell exhibits an ultra‐long cycle life (1100 h at 1.0 mA cm−2/1.0 mAh cm−2) in carbonate electrolyte. Moreover, the K full cells demonstrate enhanced cycling stability (1500 cycles at 8 C) and rate capacity (117.27 mAh g−1 at 20 C). This novel biomimetic design of composite anode presents an effective and rational approach for achieving stable PMBs. [ABSTRACT FROM AUTHOR]

Ammonia, a vital component in the synthesis of fertilizers, plastics, and explosives, is traditionally produced via the energy‐intensive and environmentally detrimental Haber–Bosch process. Given its considerable energy consumption and significant greenhouse gas emissions, there is a growing shift toward electrocatalytic ammonia synthesis as an eco‐friendly alternative. However, developing efficient electrocatalysts capable of achieving high selectivity, Faraday efficiency, and yield under ambient conditions remains a significant challenge. This review delves into the decades‐long research into electrocatalytic ammonia synthesis, highlighting the evolution of fundamental principles, theoretical descriptors, and reaction mechanisms. An in‐depth analysis of the nitrogen reduction reaction (NRR) and nitrate reduction reaction (NitRR) is provided, with a focus on their electrocatalysts. Additionally, the theories behind electrocatalyst design for ammonia synthesis are examined, including the Gibbs free energy approach, Sabatier principle, d‐band center theory, and orbital spin states. The review culminates in a comprehensive overview of the current challenges and prospective future directions in electrocatalyst development for NRR and NitRR, paving the way for more sustainable methods of ammonia production. [ABSTRACT FROM AUTHOR]

Bimetallic phosphides are considered as promising electrocatalysts for zinc–air batteries toward oxygen evolution reaction (OER) and oxygen reduction reaction (ORR). To address the semi‐conductor inherent low electronic conductivity and catalytic activity, a polymetal‐chelated strategy is employed to in situ fabricate bimetallic nanophosphides within carbon matrix anchoring by chemical bonding. The employment of biomolecule polydopamine (PDA) efficiently anchors various transition metal ions due to its strong chelating capability via inherent functional groups. Furthermore, the chelation of multi‐metal ion is proved to promote the formation of graphitic nitrogen. The bimetallic FexCoyP phosphides nanoparticles are intimately encapsulated in carbon matrix through in situ carbonization and phosphatization processes. When utilized in Zinc–air batteries, Fe0.20Co0.80P anchored within N, P co‐doped sub‐microsphere (Fe0.20Co0.80P /PNC) exhibit a maximum power density of 167 mW cm−2 and cycle life up to 270 cycles, with a round‐trip voltage of 0.955 V. The mechanisms for catalytic activity passivation are ascribed to the etching of nitrogen and oxidation of phosphorus in carbon matrix, as well as the oxidation of the surface phosphide on the sub‐microspheres. This study presents a promising candidate for advancing the further development of energy conversation catalysis. [ABSTRACT FROM AUTHOR]

Electrocatalyst plays animportant role in electrochemical ammonia synthesis by determining the nitrogen reduction reaction pathway. Featuring the inherent half‐filled 3d orbitals, ion‐based alloy electrocatalysts have been attracting much more attention owing to the controllable driving force to adsorb and activate N≡N bonds. Besides supplying unoccupied d‐orbital to accommodate lone‐pair electrons to facilitate nitrogen adsorption, donating d‐orbital electrons to nitrogen antibonding orbitals to dissociate N≡N bond is demandedas well. By palladium (Pd) to synthesize PdFe3 nano‐alloy, numerous Fe 3d orbitals can be reconstructed via charge polarization between Fe and Pd, simultaneously lowering corresponding work functions. Meanwhile, the positively charged Fesites in PdFe3 can strengthen suppress the proton adsorption by electrostatic repulsion. A considerably optimized ammonia production rate of 29.07 µg h−1 mgcat.−1 and Faradic efficiency of 22.8% are accomplished at a low overpotential of −0.2 V vs. RHE. Density functional theory combined with in‐situ ATR‐FTIR results confirmthe electrocatalytic nitrogen reduction follows the associative distalmechanism and the electron‐deficient Fe induced through Pd facilitates significantly lowering the first‐step‐protonation energy barrier of only 0.07 eV (*N2 + *H →*NNH). [ABSTRACT FROM AUTHOR]

K‐metal batteries have become one of the promising candidates for the large‐scale energy storage owing to the virtually inexhaustible and widely potassium resources. The uneven K+ deposition and dendrite growth on the anode causes the batteries prematurely failure to limit the further application. An integrated K‐metal anode is constructed by cold‐rolling K metal with a potassiphilic porous interconnected mediator. Based on the experimental results and theoretical calculations, it demonstrates that the potassiphilic porous interconnected mediator boosts the mass transportation of K‐metal anode by the K affinity enhancement, which decreases the concentration polarization and makes a dendrite‐free K‐metal anode interface. The interconnected porous structure mitigates the internal stress generated during repetitive deposition/stripping, enabling minimized the generation of electrode collapse. As a result, a durable K‐metal anode with excellent cycling ability of exceed 1, 000 h at 1 mA cm−2/1 mAh cm−2 and lower polarization voltage in carbonate electrolyte is obtained. This proposed integrated anode with fast K+ kinetics fabricated by a repeated cold rolling and folding process provides a new avenue for constructing a high‐performance dendrites‐free anode for K‐metal batteries. [ABSTRACT FROM AUTHOR]

A composite of manganese monoxide loaded onto carbon nanotubes (CNTs@MnO) has been synthesized by a facile approach, in which the CNTs form a continuous conductive network connecting the electrocatalyst MnO nanoparticles together to facilitate good electrochemical performance. The electrocatalyst MnO shows favourable rechargeability, and good phase and morphology stability in lithium oxygen batteries. Excellent cycling performance is also demonstrated, in which the terminal voltage is higher than 2.4 V after 100 cycles at 0.4 mA cm−2, with 1000 mAh g−1(composite) capacity. Therefore, this hybrid material is promising for use as a cathode material for lithium oxygen batteries. [ABSTRACT FROM AUTHOR]

A hybrid cathode material for high rate lithium ion batteries was prepared by ball-milling and spray-drying a slurry containing LiFePO 4 nanoparticles, glucose and carbon nanotubes (CNTs) in water, followed by pyrolysis at 600 °C for 6 h under a gas mixture of 5% H 2 in Ar. CNTs with a large aspect ratio form a continuous conductive network connecting the LiFePO 4 nanoparticles and amorphous carbon, which significantly reduces the electrical resistance of the cathode. The hybrid material can deliver a specific capacity of 99 mAh/g at a 50 C charge/discharge rate. An excellent cycling performance was also demonstrated, with a capacity loss of less than 10% after 450 cycles at a 10 C rate. [New Carbon Materials 2014, 29(4): 287–294] [ABSTRACT FROM AUTHOR]

The figure clearly shows that the K 0.5 MnO 2 @KTaO 3 composites obtained in this paper have excellent cycling performance by using the residual alkali on the surface as a potassium resource to form a protective perovskite-type KTaO 3 layer. The capacity retention was as high as 98.1% after 100 cycles at 100 mAh/g. [Display omitted] • Surface residual alkali reverse utilization efficiently by in-situ growing a stable KTaO 3 protective layer. • Stable interface structure avoids the element dissolution and decreases the apparent activation energy. • Surface modification protect the surface crystal structure to alleviate the phase transformation. Manganese base oxide is considered as a promising cathode material for potassium ion batteries (PIBs). However, the continuous phase transition leads to the poor stability of surface structure and its cycle life still cannot meet the increasing requirements. At the same time, because of its thermodynamic instability, residual alkali will precipitate with the increase of potassium content or exposure to humid environment, which seriously affects its performance. Surface engineering techniques are thus employed herein to modify the active material surface structure by growing a protective perovskite-type KTaO 3 layer reversely utilizing the surface residual alkali as potassium resource. The obtained K 0.5 MnO 2 @KTaO 3 composite exabits a superior cycling lifespan keeping the capacity retention high to 98.8 % after 200 cycles at 300 mAh/g. Besides increasing the environmental adaptability, the protective perovskite-type KTaO 3 layer can not only inhibit the dissolution of transition metals by stabilizing the surface crystal structure, but also accelerate the K+ diffusion by decreasing the interface activation energy between cathode and electrolyte. [ABSTRACT FROM AUTHOR]

The strategy of inducing interlayer anionic ligands in 2D MoS1.5Se0.5 nanosheets is employed to consolidate the interlayer band gap and optimize the electronic structure for the potassium ion battery. It combines complementary advantages from two kinds of anionic ligands with high conductivity and good affinity with potassium ions. The potassium ion diffusion rate is accelerated as well by an optimized lower energy barrier for ion diffusion pathways, with the formation of highly reversible KMo3Se3 crystal other than K0.4MoS2/K2MoS4, which encounters a much slower electro/ion diffusion rate upon discharging. These advances deliver enhanced potassium storage properties with excellent cycling stability, with retained specific capacity of 531.6 mAh g−1 at a current density of 200 mA g−1 even after 1000 cycles, and high rate capability with specific capacity of 270.1 mAh g−1 at 5 A g−1. The insertion and conversion mechanism are also elucidated by a combination of density functional theory computations and in situ synchrotron measurements. [ABSTRACT FROM AUTHOR]

Double carbon-embedded Na3V2(PO4)3 (DC-NVP) nanocomposites were prepared via in situ growth of NVP@C nanoparticles on carbon nanotubes (CNTs). Beneficial of a high electronic conductivity network and structure stability, the DC-NVP nanocomposite as an anode of sodium ion batteries (SIBs) reveals outstanding electrochemical properties, delivering ultra-long cycle life with a first charge capacity of 78 mA h g−1 at 50 C and a capacity loss of 0.006%/cycle over 8000 cycles. The NVP//NVP full cells, fabricated by the DC-NVP nanocomposites as bipolar electrode, exhibit a discharge capacity of 72.1 mA h g−1 at 20 C after 5000 cycles and a corresponding capacity retention of 81%. The remarkable performance of DC-NVP nanocomposites is ascribed to that of the unique double carbon-embedded nanostructure, which possesses good electronic conductivity, larger electrode-electrolyte contact area, fast electron and ion transportation, and structural stability. [ABSTRACT FROM AUTHOR]

The potassium dual-ion batteries (DIBs) have been attracting a great attention in recent years due to their promising environmental benignancy, high energy density, and long lifespan. The active materials based on conversion reaction mechanism are favorable and widely expected to alleviate the dendrite formation, red phosphorous was thus employed and fabricated into a three-dimensional porous carbon matrix anchored by P– O –C chemical bonding using vaporization–condensation–conversion process. Meanwhile, the elements modified carbon can not only guarantee the electronic conductivity and ions diffusion, but also alleviate the red phosphorous volumetric expansion and detachment. When coupled with graphite, the K-DIBs demonstrate excellent electrochemical performance with a high 213 Wh kg−1 energy density and a promising stability up to 650 cycles. This explored material will provide highly relevant insights for next-generation advanced energy storage systems. • New explored red phosphorous structure for potassium dual-ion batteries. • Inducing P– O –C chemical bonding to anchor red phosphorous for electronic conductivity and structure stability. • Excellent energy density of 213 Wh kg−1 and superior lifespan up to 650 cycles. [ABSTRACT FROM AUTHOR]

Abstract: An integrated, free‐standing, and binder‐free type of flexible anode electrode is fabricated from numerous holey‐structured, 2D nickel‐based phosphide nanosheets connected with carbon nanotubes. This electrode architecture can not only uniformly disperse the nanosheets throughout the whole electrode to avoid aggregation or detachment, but also provide an ideal sodium ion and electrolyte diffusion and penetration network with high electronic conductivity. Meanwhile, bimetallic phosphide formation by introducing secondary metal species will lead to a synergistic effect to modify the electrochemical properties. Due to the excellent compositional and structural characteristics of this electrode, it delivers superior performance. This designed flexible anode with Ni1.5Co0.5Px nanosheets demonstrates a reversible capacity of 496.4 mAh g−1 at 0.5 C and a good rate capacity of 276.1 mAh g−1 at 8 C. Meanwhile, this connected integrated network woven from carbon nanotubes can effectively restrain volumetric expansion and shrinkage, and affect the conversion reaction products formation as well, from large‐sized microspheres to film structure, which is primarily credited with the improvement in electrochemical performance. This work may open up a new path for the synthesis of morphology‐controlled phosphides and promote the further development of flexible devices. [ABSTRACT FROM AUTHOR]

A serials of micro-sized Li 3− x Na x V 2 (PO 4 ) 3 /C composite has been synthesized by sol-gel method, comprised of numerous primary nanocrystals. This structure can efficiently facilitate lithium-ion transport in secondary aggregated individual particles due to the short diffusion distance among primary nanocrystals, along with a high tap density. With the increasing of Na doping content, the structure evolution occurs in Li 3- x Na x V 2 (PO 4 ) 3 from a single-phase structure to a two-phase structure. The appearance of rhombohedral phase can provide a larger free volume of the interstitial space, fastening ionic movement to offer an excellent high rate capability. Furthermore, Na doping can stabilize the rhombohedral structure of the V 2 (PO 4 ) 3 framework, leading to the remarkable cycling stability. Among all the composites, Li 2.6 Na 0.4 V 2 (PO 4 ) 3 /C presents the best electrochemical performance with a high energy density of 478.8 Wh kg −1 , delivering high initial discharge capacities of 121.6, 113.8 and 109.7 mAh g −1 at the rate of 5 C, 10 C and 20 C in a voltage range of 3.0 – 4.3 V, respectively. It also exhibit an excellent high rate cycling performance, with capacity retention of 85.9 %, 81.7 % and 76.5 % after 1000 cycles at the rate of 5 C, 10 C and 20 C in a voltage range of 3.0 – 4.3 V. [ABSTRACT FROM AUTHOR]

• A new phosphate family member ZnMn 2 (PO 4) 2 was explored and used as cathode material in both aqueous and nonaqueous ZIBs system. • Zn2+ diffusion behaviors within ZnMn 2 (PO 4) 2 contribute the electrochemical capacity and the ions diffusion coefficient has a same level as that of Li+ within LiFePO 4. • The superior electrochemical performance of ZnMn 2 (PO 4) 2 @C composite results from the low activation energy. Exploring an appropriate and economical efficient cathode material for zinc ion batteries plays an important role in overcoming current existing challenges and realizing final practical application. A novelty explored phosphate ZnMn 2 (PO 4) 2 coated by a thin carbon layer [ZnMn 2 (PO 4) 2 @C] was synthesized and employed as cathode material for both aqueous and nonaqueous zinc storage system, featuring with a tunnel structure and working as a host for the Zn2+ extraction and insertion. It shows a reversible specific capacity of 67 mA h g−1 in 1 M Zn(CF 3 SO 3) 2 aqueous system. When coupling with FePO 4 , the full batteries containing ZnMn 2 (PO 4) 2 @C presented a capacity of 174 mA h g−1 with a high voltage plateaus of 1.17 V vs. Zn/Zn2+ in Zn(TFSI) 2 nonaqueous electrolyte. The Zn2+ diffusion behavior for ZnMn 2 (PO 4) 2 contributes the main electrochemical process and the diffusion coefficient is in a scope of 10−11–10–14 cm2 s−1 for aqueous system and 10−12–10–14 cm2 s−1 for nonaqueous system, respectively. Combined with the high thermal stability, the low ion apparent activation energy and high diffusion coefficient can guarantee the superior electrochemical performance. A new phosphate family member for next-generation aqueous and nonaqueous zinc ion batteries was explored. [ABSTRACT FROM AUTHOR]

• New explored two-dimensional NbSSe material for low temperature SIBs. • Inducing interlayer anionic ligands strategy. • Consolidate the interlayer band gap and optimize the electronic structure. • Excellent rate capability and lifespan can be exhibited at 0 °C. Sodium ion batteries performance at low temperature is extremely restricted by the sluggish kinetics of sodium ions diffusion within active materials and interface. The strategy of inducing interlayer anionic ligands in two-dimensional NbSSe nanoplates is employed to consolidate the interlayer band gap and optimize the electronic structure. It combines complementary benefits from two kinds of anionic ligands with high conductivity and good affinity with sodium ions at low temperature. The explored two-dimensional NbSSe nanoplates can provide an acceptable rate and lifespan electrochemical performance, delivering a high reversible capacity of 136 mAh g−1 at 0 °C with the 92.67% retention after 500 cycles at 0.2 C. The totally sodium storage capacity are contributed from the combination of capacitive and diffusion behaviours. The sodium ion diffusion coefficients are in the range of 3.23 × 10-13 to 4.47 × 10-12 at 0 °C. The diffusion apparent activation energy is 54.92 kJ mol−1 and the activation energy is 65.97 kJ mol−1. The explored two-dimensional NbSSe nanoplates can extend the sodium ion battery application field, particularly at low temperatures. [ABSTRACT FROM AUTHOR]

• A dense Zn-Al-LDHs anode protection layer can efficiently avoid the additional reaction and growth of zinc dendrites. • The hydrophilic and anticorrosive property of Zn-Al-LDHs protection layer has a lower nucleation/dissolution energy barrier. • The lower surface area and adsorption capability of the dense protection layer can effectively shorten the ion transport path and improve kinetic. Rechargeable aqueous zinc ion batteries have attracted increasing attention for large-scale energy storage system. Restricted by the zinc deposition and dendrite growth, the practical application was hindered seriously by the poor rechargeability and instability. The strategy of utilizing Zn-Al-layered double hydroxides hexagonal nanoplates modifying zinc metal anode was employed by a scalable method of spinning coating. This integrated electrode can not only realize ions well-distributed reaction on the electrode surface due to the dense protection layer weak adsorption behavior and low surface area, but also can efficiently avoid excessive zinc deposition and growth of zinc dendrites. The nucleation and dissolution energy barriers in the phase transition between zinc ions and the integrated electrode are decreased as well. The integrated electrode harvests a long-term stability of 1000 h at 1.0 mA h cm-2 and effectively suppresses side reactions in the Zn//Zn symmetric cells. In addition, coupled with MnO 2 as full cell, the capacity remains 195 mA h g-1 with the retention of 81.2% after 200 cycles. It is promising that the employed scalable strategy will provide new pathway into Zn metal anode protection and accelerate the practical application of aqueous zinc ion batteries. [ABSTRACT FROM AUTHOR]

Heteroatom doping carbonaceous materials are of great significance in potassium-ion batteries. In this work, a special iodine-/ nitrogen- dual-doped hard carbon (I/N-HC) material is successfully synthesized. In contrast to single-substitutional N dopant atoms, the I dopant presents two configurations of I 3 − and I 5 − adsorbed on the surface of carbon plane. Both I -doping and N -doping could provide more K -ions storage sites. Furthermore, the enhanced interlayer distance by I -doped and strongly K -ion adsorption energy of I/N codoping (about -4.00 eV), would favor the adsorption of K ions. When used as K -ion batteries anodes, I/N-HC can be maintained a reversible capacity of 149 mAh g−1 over 400 cycles at 500 mA g−1, and an outstanding rate capability of 150 mAh g−1 at 800 mA g−1. This work offers a new type of iodine doping, and reveal the mechanism of I/N co-doping carbon materials for K -ion batteries. [ABSTRACT FROM AUTHOR]

A novel ion-permselective separator comprised the top layer of LiX zeolite membrane and the support layer of commercial Celgard membrane, namely LiX@Celgard, was prepared and employed for the first time in Li–S battery. The LiX zeolite membrane was obtained via the in situ hydrothermal synthesis of NaX zeolite over the X-type zeolite-seeded Celgard membrane and the subsequent Li+ ion-exchange. The characterizations of LiX/Celgard separator by means of XRD, SEM, EDS and XPS showed that a continuous and compact layer of LiX zeolite crystals, with a thickness of ca. 6 μm, has been tightly grafted over the surface of Celgard support. The LiX@Celgard separator was proved to possess an improved electrolyte wettability and high efficiency for inhibiting the penetration of polysulfide (PSs). The electrochemical performance determination indicated that the Li-ion conductivity, diffusion coefficient and transference number were all larger for the battery basing on the LiX/Celgard separator than for that basing on the pristine Celgard separator. The above superior properties of LiX/Celgard separator restrained significantly the shuttle of PSs and improved obviously the efficiency in the utilization of sulfur. At a C-rate of 0.2 C, a specific capacity of ca. 1083 mAh/g, with a capacity retention of 70% after 400 cycles, had been achieved for the Li–S battery employing the LiX/Celgard separator. The strategy adopted in this work can be an enlightenment for the development of ion-selective membranes used in rechargeable battery and other energy storage field. On the one hand, Li ions serve as the counterions of LiX zeolite, and thus they can migrate freely across the membrane; on the other hand, the soluble PSs (Li 2 S x , 4 ≤ x ≤ 8) possess an obviously larger size (11–12 Å) than the pore size of X zeolite (7.4 Å), so they are uncapable to diffusion through LiX zeolite membrane. Therefore, LiX zeolite membrane can efficiently suppress the shuttle effect during the charge/discharge process, enabling the Li–S battery to exhibit a stable long-term cycle performance. Image 1 • Modification of commercial Celgard separator via in situ growth of LiX zeolite membrane. • Use of LiX zeolite membrane-modified Celgard separator for the first time in Li–S battery. • Promotion on Li–S battery performance by LiX zeolite membrane-modified Celgard separator. [ABSTRACT FROM AUTHOR]

Brain age prediction models using diffusion magnetic resonance imaging (dMRI) and machine learning techniques enable individual assessment of brain aging status in healthy people and patients with brain disorders. However, dMRI data are notorious for high intersite variability, prohibiting direct application of a model to the datasets obtained from other sites. In this study, we generalized the dMRI-based brain age model to different dMRI datasets acquired under different imaging conditions. Specifically, we adopted a transfer learning approach to achieve domain adaptation. To evaluate the performance of transferred models, brain age prediction models were constructed using a large dMRI dataset as the source domain, and the models were transferred to three target domains with distinct acquisition scenarios. The experiments were performed to investigate (1) the tuning data size needed to achieve satisfactory performance for brain age prediction, (2) the feature types suitable for different dMRI acquisition scenarios, and (3) performance of the transfer learning approach compared with the statistical covariate approach. By tuning the models with relatively small data size and certain feature types, optimal transferred models were obtained with significantly improved prediction performance in all three target cohorts (p ​< ​0.001). The mean absolute error of the predicted age was reduced from 13.89 to 4.78 years in Cohort 1, 8.34 to 5.35 years in Cohort 2, and 8.74 to 5.64 years in Cohort 3. The test–retest reliability of the transferred model was verified using dMRI data acquired at two timepoints (intraclass correlation coefficient ​= ​0.950). Clinical sensitivity of the brain age prediction model was investigated by estimating the brain age in patients with schizophrenia. The prediction made by the transferred model was not significantly different from that made by the reference model. Both models predicted significant brain aging in patients with schizophrenia as compared with healthy controls (p ​< ​0.001); the predicted age difference of the transferred model was 4.63 and 0.26 years for patients and controls, respectively, and that of the reference model was 4.39 and −0.09 years, respectively. In conclusion, transfer learning approach is an efficient way to generalize the dMRI-based brain age prediction model. Appropriate transfer learning approach and suitable tuning data size should be chosen according to different dMRI acquisition scenarios. [ABSTRACT FROM AUTHOR]

Encapsulating SexS8−x into vertically‐aligned carbon nanotubes co‐doped with boron and nitrogen, yields a three‐dimensional selenium sulfide@carbon nanotube array. As Xiao‐Hua Chen, Wen‐Bin Luo, and co‐workers describe in article number 1805018, such arrays enable fast migration to realize excellent rate capability and efficient utilization of the SexS8−x loaded inside. Volumetric expansion and the polysulfide shuttling phenomenon during the cycling process are reduced, enabling excellent lithium storage capability. [ABSTRACT FROM AUTHOR]

A 3D selenium sulfide@carbon nanotube array is designed and synthesized by encapsulating and anchoring a large amount of selenium sulfide (SexS8−x) into boron‐ and nitrogen‐codoped vertically aligned carbon nanotubes. Successfully employed as cathode material for the lithium metal battery, it exhibits long cycling lifetime and high rate capability with high energy density. Vertically aligned carbon nanotubes can not only enable fast migration to realize excellent rate capability and efficient utilization of the SexS8−x loaded inside, but also provide optimal unidirectional void space to significantly reduce volumetric expansion and the polysulfide shuttling phenomenon during the cycling process. Meanwhile, the graphene layers decorated by element doping and held together by COOH‐ and OH‐enriched poly(acrylic acid) binder can efficiently consolidate SexS8−x molecules inside the carbon nanotubes and prevent the separation of the active materials from the current collector during long‐term cycling. Benefiting from these features, the composite presents optimal cycling performance with a high initial Coulombic efficiency of 96% and a high reversible capacity of 818 mAh g−1 after 500 cycles at a current density of 500 mA g−1. This composite thus represents one of the most promising cathode materials that can give the lithium metal battery long cycle life and remarkable power density. A 3D selenium sulfide@carbon nanotube array is designed and synthesized by encapsulating and anchoring a large amount of selenium sulfide (SexS8−x) into boron‐ and nitrogen‐codoped vertically aligned carbon nanotubes. This architecture caters to practical application with a satisfactory rate capability and long lifespan by allievating volumetric change during the full lithiation process and enhancing the electric conductivity of intermediate product. [ABSTRACT FROM AUTHOR]

An integrated, free‐standing, and binder‐free type of flexible anode electrode is fabricated from numerous holey‐structured, 2D nickel‐based phosphide nanosheets connected with carbon nanotubes. This electrode architecture can not only uniformly disperse the nanosheets throughout the whole electrode to avoid aggregation or detachment, but also provide an ideal sodium ion and electrolyte diffusion and penetration network with high electronic conductivity. Meanwhile, bimetallic phosphide formation by introducing secondary metal species will lead to a synergistic effect to modify the electrochemical properties. Due to the excellent compositional and structural characteristics of this electrode, it delivers superior performance. This designed flexible anode with Ni1.5Co0.5Px nanosheets demonstrates a reversible capacity of 496.4 mAh g−1 at 0.5 C and a good rate capacity of 276.1 mAh g−1 at 8 C. Meanwhile, this connected integrated network woven from carbon nanotubes can effectively restrain volumetric expansion and shrinkage, and affect the conversion reaction products formation as well, from large‐sized microspheres to film structure, which is primarily credited with the improvement in electrochemical performance. This work may open up a new path for the synthesis of morphology‐controlled phosphides and promote the further development of flexible devices. An integrated, free‐standing, and binder‐free type of flexible anode electrode is fabricated from numerous holey‐structured, 2D nickel‐based phosphide nanosheets connected with carbon nanotubes. This electrode architecture can not only uniformly disperse the nanosheets throughout the whole electrode to avoid aggregation or detachment, but also provide an ideal sodium ion and electrolyte diffusion and penetration network with high electronic conductivity. [ABSTRACT FROM AUTHOR]

In article number 1801016, Ji Liang, Jia‐Feng Zhang, Wen‐Bin Luo, and co‐workers fabricate an integrated, free‐standing, and binder‐free flexible anode electrode from numerous holey‐structured, two‐dimensional, nickel‐based phosphide nanosheets connected with carbon nanotubes. This electrode architecture can not only uniformly disperse the nanosheets throughout the whole electrode to avoid aggregation or detachment, but also provides an ideal sodium‐ion and electrolyte diffusion and penetration network with high electronic conductivity. [ABSTRACT FROM AUTHOR]