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Abstract: Layered transition metal sulfides (LTMSs) have tremendous commercial potential in anode materials for sodium‐ion batteries (SIBs) in large‐scale energy storage application. However, it is a great challenge for most LTMS electrodes to have long cycling life and high‐rate capability due to their larger volume expansion and the formation of soluble polysulfide intermediates caused by the conversion reaction. Herein, layered CuS microspheres with tunable interlayer space and pore volumes are reported through a cost‐effective interaction method using a cationic surfactant of cetyltrimethyl ammonium bromide (CTAB). The CuS–CTAB microsphere as an anode for SIBs reveals a high reversible capacity of 684.6 mAh g−1 at 0.1 A g−1, and 312.5 mAh g−1 at 10 A g−1 after 1000 cycles with high capacity retention of 90.6%. The excellent electrochemical performance is attributed to the unique structure of this material, and a high pseudocapacitive contribution ensures its high‐rate performance. Moreover, in situ X‐ray diffraction is applied to investigate their sodium storage mechanism. It is found that the long chain CTAB in the CuS provides buffer space, traps polysulfides, and restrains the further growth of Cu particles during the conversion reaction process that ensure the long cycling stability and high reversibility of the electrode material. [ABSTRACT FROM AUTHOR]

Abstract: One-dimensional semiconductor nanostructures have demonstrated significant advantages for electrochemical electrode due to their remarkable size-dependent and structure-related properties. In this work, large-scale single-crystalline SnO2 nanowires have been successfully synthesized by thermal evaporation of a SnO2 and C powder under atmospheric conditions without any carrier gas or noble metal catalysts-coated substrate. The as-prepared samples exhibit uniform morphology with a thin diameter of 100–200 nm and length up to several tens of micrometers. The SnO2 nanowires directly grown on the initially deposition layer are found to grow along [301] direction, which is possibly dominated by a vapor–solid (VS) mechanism. The SnO2 nanowires synthesized by this simple and cheap method deliver a very high lithium storage capacity with good cycle stability and high rate capability, allowing for the achievement of high energy density and long cycle life for the next-generation energy conversion and storage devices. [Copyright &y& Elsevier]

Using aniline as monomer, ammonium persulfate as initiator, ZnCl2 and FeCl3 as metal sources, ZnFe-PANI catalyst precursor was prepared by one-step in-situ chemical polymerization method, and then ZnFe-N-C catalyst was synthesized by high temperature pyrolysis-acidification-secondary pyrolysis. The morphology and structure of the catalyst were characterized by XRD, SEM, Raman and other methods, and its catalytic performance was investigated by the electroreduction reaction of CO2. The results showed that metal doping had little effect on the morphology and structure of N-C materials, but enhanced its structural stability, increased the number of defect sites and active sites, and the area of electrochemical activity, which was conducive to the improvement of reaction performance; When the molar ratio of Zn and Fe was 3 : 1 in the precursor, the obtained sample ZnFe-N-C-3-1 had the best catalytic performance. At an overvoltage of 0.5V, the Faraday efficiency of the CO2 product by electroreduction was as high as 55 %. [ABSTRACT FROM AUTHOR]

• An experiment was built to simulate leaks in an industrial scale experimental pipeline. • The effects of orifice size, pipeline pressure, and liquid flow speed were investigated. • An artificial neural network model was developed for leaks prediction. Water pipeline leakage is a common and significant global problem. In-pipe inspection based on hydrophone is one of the most direct, accurate, and reliable solutions for leak detection and recognition. In this study, a scheme of in-pipe detector was designed to pick up and identify acoustic signal due to leak. To investigate the characteristic of acoustic signal, an experimental platform was built to simulate the leaks and obtain acoustic signals under different leak conditions in an industrial scale water pipeline. Because a decreased pressure as leak has an unstable fluctuation in time domain, the frequency composition of the signal was analyzed in frequency domain, and then the change of frequency amplitude can be referenced to recognize the leaks. Moreover, the effects of leak size, pipeline pressure, and water flow rate on the characteristic of acoustic signal were investigated. The results show that the signal's intensity under leak conditions are significantly higher than that of no leak case, and it will increase as the increased leak size; the signal intensity under no leak case will increase with the growth of pipeline pressure; the flow velocity has little effect on the signal intensity. To increase the recognition accuracy, an artificial neural network model was developed for the leak prediction, and 18 cases through additional tests were selected to validate the accuracy of model. Comparing experimental and prediction results, maximum relative error is within 10.0%. It indicates that the prediction model has a reasonable accuracy for the leak recognition. [ABSTRACT FROM AUTHOR]

[Display omitted] • A new operando non-topological conversion strategy of the ZnIn 2 S 4. • The obtained ZnO@In 2 O 3 as the nickel-zinc battery anode exhibits the enhanced performance. • This work provides a novel strategy to construct high-performance electrode materials. Nickel-zinc batteries have obvious advantages such as high safety, environmental friendship, and high energy density, making them as the most promising alternatives to replace the traditional lead-acid batteries. However, the notorious zinc dendrite issue seriously hinders the development of the nickel-zinc battery. Considering In 2 O 3 can inhibit zinc dendrite effectively, hence it is important to obtain the zinc electrode with uniformly dispersed In 2 O 3. Here, via applying an operando non-topological conversion reaction of ZnIn 2 S 4 , the zinc oxide composite anode with evenly distributed In 2 O 3 can be constructed. Through a series of characterizations such as X-ray diffraction, scanning/transmission electron microscopes, and X-ray photoelectron spectroscopy, the operando non-topological conversion reaction from ZnIn 2 S 4 precursor to ZnO@In 2 O 3 can be directly demonstrated. Meanwhile, as the nickel-zinc battery anode, the obtained ZnO@In 2 O 3 can achieve the high specific capacity (520 mAh g−1), high rate performance, and long cycle stability. This operando non-topological conversion strategy provides a new approach for designing the high-performance electrode materials. [ABSTRACT FROM AUTHOR]

VO 2 (B) is a promising cathode candidate for aqueous zinc ion batteries owing to its special tunnel lattice structure. However, the zinc storage mechanisms of VO 2 (B) are elusive over large voltage range, especially at the high potential. Via combined structure and composition characterizations such as X-ray diffraction, scanning electron microscopy, transmission electron microscopy, and X-ray photoelectron spectroscopy as well as electrochemical tests, it is demonstrated that VO 2 (B) goes through a conversion reaction when the potential approaching about 1.5 V during the first charging process. The obtained conversion product Zn 3 (OH) 2 V 2 O 7 ·2H 2 O shows high zinc ion storage capacity of 330 mA h g−1 at 0.1 A g−1, fast zinc ion diffusion kinetics, and high rate performances (130 mA h g−1 at 10 A g−1). This work provides a novel strategy for the rational design of electrode materials with large voltage range, especially for aqueous multi-valence ion batteries. Image 1 • A new in-situ electrochemical conversion mechanism of the VO 2 (B) cathode is proposed. • The conversion product Zn 3 (OH) 2 V 2 O 7 ·2H 2 O exhibits the enhanced battery performances. • This work provides a novel strategy to design electrode materials with large voltage range. [ABSTRACT FROM AUTHOR]

Developing single-atomic catalysts with superior selectivity and outstanding stability for CO 2 electroreduction is desperately required but still challenging. Herein, confinement strategy and three-dimensional (3D) nanoporous structure design strategy are combined to construct unsaturated single Ni sites (Ni-N 3 ) stabilized by pyridinic N-rich interconnected carbon nanosheets. The confinement agent chitosan and its strong interaction with g-C 3 N 4 nanosheet are effective for dispersing Ni and restraining their agglomeration during pyrolysis, resulting in ultrastable Ni single-atom catalyst. Due to the confinement effect and structure advantage, such designed catalyst exhibits a nearly 100% selectivity and remarkable stability for CO 2 electroreduction to CO, exceeding most reported state-of-the-art catalysts. Specifically, the CO Faradaic efficiency (FE CO ) maintains above 90% over a broad potential range (-0.55 to -0.95 V vs. RHE) and reaches a maximum value of 99.6% at a relatively low potential of -0.67 V. More importantly, the FE CO is kept above 95% within a long-term 100 h electrolyzing. Density functional theory (DFT) calculations explain the high selectivity for CO generation is due to the high energy barrier required for hydrogen evolution on the unsaturated Ni-N 3 . This work provides a new designing strategy for the construction of ultrastable and highly selective single-atom catalysts for efficient CO 2 conversion., (© 2023 Wiley‐VCH GmbH.)

Aqueous zinc-ion batteries have obtained broad attention due to their high safety, eco-friendliness, and low cost. However, they are still in the developing stage considering the limited candidate of high-performance cathode materials. Furthermore, the intrinsic storage zinc mechanism is also needed to uncover. Here, we propose an operando crystal-amorphous transformation of tunnel-type VOOH and the obtained amorphous V 2 O 5 serves as a high-performance zinc-ion battery cathode. In-situ X-ray diffraction corroborates the unique operando crystal-amorphous transformation of VOOH during the initial charging process. X-ray photoelectron spectroscopy and transmission electron microscopy further demonstrate the element valence evolution and the lattice structure change, respectively. The operando electrochemical crystal-amorphous transformation allows the obtained amorphous V 2 O 5 to achieve the high capacity of ∼ 350.7 mAh g -1 , rate performance (151.2 mAh g -1 at 6.4 A g -1 ), energy and power densities (137 Wh kg -1 at 6831 W kg -1 ), unveiling a promising approach of cathode materials via operando crystal-amorphous transformation to achieve the enhanced zinc storage., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier Inc. All rights reserved.)

In view of the importance of multifunctional catalysts that can drive different electrocatalytic reactions in the same electrolyte solution, we designed and prepared a series of multicomponent nanohybrids composed of Co 9 S 8 and MoS 2 derived from cobalt-doped polyoxometalate (Co-POMs) by one-pot calcination method. The obtained Co 9 S 8 @MoS 2 nanohybrids were composed of Co 9 S 8 , MoS 2 , Co-Mo-S phases and assembled nanosheets, and therefore were explored as trifunctional electrocatalysts for hydrogen evolution reaction, oxygen evolution reaction, and methanol oxidation reaction (MOR) in an alkaline medium. The nanostructure and chemical components of the series of Co 9 S 8 @MoS 2 nanohybrids can be modulated by changing the mole ratios of H 5 Mo 12 O 41 P to Co(NO 3 ) 2 precursor. Compared with the sole component and other reported Co 9 S 8 @MoS 2 nanohybrids, the Co 9 S 8 @MoS 2 nanohybrid prepared from the 1:1 ratio of PMo 12 and Co(NO 3 ) 2 exhibited superior MOR catalysis efficiency (121.4 mA cm -2 ) and an extremely low overpotential (1.49 V) for overall water splitting at a current density of 10 mA cm -2 owning to the effective synergism among Co 9 S 8 , MoS 2 , and Co-Mo-S phase. Overall, this study provides a feasible approach to developing efficient and stable trifunctional bimetal electrocatalysts for clean-energy applications., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 Elsevier Inc. All rights reserved.)

It is always challenging to fabricate two-dimensional transition-metal dichalcogenides into multiple hollow micro-/nanostructures with improved properties for various potential applications. Here, hierarchically porous MoS 2 -C hollow rhomboids (MCHRs) have been creatively synthesized via a facile self-templated solvothermal approach. It has been clarified that the obtained MCHRs assembled beneath ultrathin γ-MnS and carbon cohybridized MoS 2 nanosheets under the structural direction of the MnMoO 4 ·0.49H 2 O self-template. The prepared MCHR anode of sodium-ion batteries exhibited a reversible capacity of 506 mA h g -1 at 0.1 A g -1 , ultrahigh rate capabilities up to 10 A g -1 with 310 mA h g -1 , and exceptional stability over 3000 cycles. This study provides inspiration for the rational design of hierarchically porous hollow nanostructures with specific geometries as an excellent electrode material for outstanding performance energy storage equipment.

Highly Li+-conductive HfNb24O62 is explored as a new intercalation-type niobium-based oxide anode material for superior Li+ storage. HfNb24O62 owns a Wadsley-Roth shear structure with a large unit-cell volume, leading to a large Li+ diffusion coefficient. HfNb24O62 shows a large capacity, safe operating potential, high rate performance and good cyclability.

Based on both the compatibility principle of similar polymeric structures and the steric interaction, a polyether amine (D2000) modified MOF (UIO-66) was dispersed into an ionic liquid with a polyether structure to form a new porous liquid (called the UIO-66-liquid) at room temperature. This unique UIO-66-liquid showed an outstanding CO2 uptake capacity among the existing porous liquids.

Rechargeable magnesium batteries (rMBs) are promising as the most ideal further energy storage systems but lack competent cathode materials due to sluggish redox reaction kinetics. Herein, developed is an anionic Se-substitution strategy to improve the rate capability and the cycling stability of 2D CuS 1- x Se x nanosheet cathodes through an efficient microwave-induced heating method. The optimized CuS 1- x Se x (X = 0.2) nanosheet cathode can exhibit high reversible capacity of 268.5 mAh g -1 at 20 mA g -1 and good cycling stability (140.4 mAh g -1 at 300 mA g -1 upon 100 cycles). Moreover, the CuS 1- x Se x (X = 0.2) nanosheet cathode can deliver remarkable rate capability with a reversible capacity of 119.2 mAh g -1 at 500 mA g -1 , much higher than the 21.7 mAh g -1 of pristine CuS nanosheets. The superior electrochemical performance can be ascribed to the enhanced reaction kinetics, enriched cation storage active sites, and shortened ion diffusion pathway of the CuS 1- x Se x nanosheet. Therefore, tuning anionic chemical composition demonstrates an effective strategy to develop novel cathode materials for rMBs., (© 2019 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Highly wrinkled graphene film (HWGF) with high packing density was synthesized by combining an electrostatically self-assembling process, a vacuum filtration-induced film assembling process and capillary compression. Fe 3 O 4 nanoparticles were used as a low-cost and environment-friendly hard template. Hierarchical porosity and high packing density were achieved with the aid of capillary compression in the presence of Fe 3 O 4 nanoparticles. This strategy enables integration of highly wrinkled graphene sheets to form highly compact carbon electrodes with a continuous ion transport network. The generated HWGF exhibited a high packing density of 1.53 g cm -3 , a high specific surface area of 383 m 2 g -1 and a hierarchically porous structure. The HWGF delivered a high capacitance of 242 F g -1 and 370 F cm -3 at 0.2 A g -1 in 6 M KOH aqueous electrolyte system with excellent rate capability (202 F g -1 and 309 F cm -3 retained at 20 A g -1 ). The capacity retention rate reached 97% after 10 000 cycles at 1 A g -1 . The HWGF-based supercapacitor exhibited a high energy density of 17 W h kg -1 at the power density of 49 W kg -1 . Such high capacitive performances could be attributed to the highly dense but porous graphene assemblies composed of highly wrinkled graphene sheets., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

An efficient hydrogen evolution reaction (HER) depends essentially on high-performing electrocatalysts. The aggregation of catalysts normally deteriorates their activity and stability. In this study, a two-step route was used to synthesize surface intercalated well-dispersed spherical MoS 2x Se 2(1-x) nanocatalysts. The resulting catalysts present a highly active and stable performance towards the HER with an overpotential of -143 mV at 10 mA cm -2 , and a Tafel slope of 53.8 mV dec -1 . The mechanism for the enhanced HER was analyzed and was attributed to three factors: (i) large numbers of defects and edge active sites arising from the coexistence of S and Se elements; (ii) enhanced electric conductivity arising from the phase transition from the semiconducting 2H-phase to metallic 1T-phase during the intercalation process; and (iii) enlarged contact areas between active sites and electrolyte caused by the increased surface roughness due to the surface intercalation. This work not only deepens our understanding of the improved HER performance of surface intercalated catalysts, but also provides novel strategies for preparing durable electrocatalysts through surface engineering.