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Abstract Aqueous Zn-I flow batteries utilizing low-cost porous membranes are promising candidates for high-power-density large-scale energy storage. However, capacity loss and low Coulombic efficiency resulting from polyiodide cross-over hinder the grid-level battery performance. Here, we develop colloidal chemistry for iodine-starch catholytes, endowing enlarged-sized active materials by strong chemisorption-induced colloidal aggregation. The size-sieving effect effectively suppresses polyiodide cross-over, enabling the utilization of porous membranes with high ionic conductivity. The developed flow battery achieves a high-power density of 42 mW cm−2 at 37.5 mA cm−2 with a Coulombic efficiency of over 98% and prolonged cycling for 200 cycles at 32.4 Ah L−1 posolyte (50% state of charge), even at 50 °C. Furthermore, the scaled-up flow battery module integrating with photovoltaic packs demonstrates practical renewable energy storage capabilities. Cost analysis reveals a 14.3 times reduction in the installed cost due to the applicability of cheap porous membranes, indicating its potential competitiveness for grid energy storage.

Abstract The high redox potential of Zn0/2+ leads to low voltage of Zn batteries and therefore low energy density, plaguing deployment of Zn batteries in many energy-demanding applications. Though employing high-voltage cathode like spinel LiNi0.5Mn1.5O4 can increase the voltages of Zn batteries, Zn2+ ions will be immobilized in LiNi0.5Mn1.5O4 once intercalated, resulting in irreversibility. Here, we design a polymer hetero-electrolyte consisting of an anode layer with Zn2+ ions as charge carriers and a cathode layer that blocks the Zn2+ ion shuttle, which allows separated Zn and Li reversibility. As such, the Zn‖LNMO cell exhibits up to 2.4 V discharge voltage and 450 stable cycles with high reversible capacity, which are also attained in a scale-up pouch cell. The pouch cell shows a low self-discharge after resting for 28 days. The designed electrolyte paves the way to develop high-voltage Zn batteries based on reversible lithiated cathodes.

Gas–liquid flow in the dissolved air flotation (DAF) tank was studied through computational fluid dynamics through the realizable k-ε model and the population balance model (PBM) to predict the gas content of different flotation mediums (air, carbon dioxide, and chlorine) at different heights of the separation zone in the DAF tank. Simultaneously, a particular focus was placed on studying the effects of bubble aggregation and breakage on gas content. The results indicated that there were virtually no bubbles present in the region below 0.1 m of the separation zone. The gas content in the separation zone could meet the needs for gas content in the DAF tank when all these three gases were adopted as flotation medium. The introduction of models for bubble aggregation and breakage resulted in lower gas content at the bottom of the separation zone and higher gas content at the top, aligning more closely with experimental data. Due to the structural similarity and similar physicochemical characteristics of carbon dioxide and water molecules, the impact of bubble aggregation and breakage on the gas content is minimal. HIGHLIGHTS Considering the aggregation and breakage of bubbles during simulation.; Introducing the population balance model to consider non-uniform-sized bubbles.; Study the hydraulic characteristics of the separation zone when adopting air, carbon dioxide, and chlorine gas as flotation medium.;

Abstract Most current research is devoted to electrochemical nitrate reduction reaction for ammonia synthesis under alkaline/neutral media while the investigation of nitrate reduction under acidic conditions is rarely reported. In this work, we demonstrate the potential of TiO2 nanosheet with intrinsically poor hydrogen-evolution activity for selective and rapid nitrate reduction to ammonia under acidic conditions. Hybridized with iron phthalocyanine, the resulting catalyst displays remarkably improved efficiency toward ammonia formation owing to the enhanced nitrate adsorption, suppressed hydrogen evolution and lowered energy barrier for the rate-determining step. Then, an alkaline-acid hybrid Zn-nitrate battery was developed with high open-circuit voltage of 1.99 V and power density of 91.4 mW cm–2. Further, the environmental sulfur recovery can be powered by above hybrid battery and the hydrazine-nitrate fuel cell can be developed for simultaneously hydrazine/nitrate conversion and electricity generation. This work demonstrates the attractive potential of acidic nitrate reduction for ammonia electrosynthesis and broadens the field of energy conversion.

Abstract Zn‐ion batteries are regarded as the most promising batteries for next‐generation, large‐scale energy storage because of their low cost, high safety, and eco‐friendly nature. The use of aqueous electrolytes results in poor reversibility and leads to many challenges related to the Zn anode. Electrolyte additives can effectively address many such challenges, including dendrite growth and corrosion. This review provides a comprehensive introduction to the major challenges in and current strategies used for Zn anode protection. In particular, an in‐depth and fundamental understanding is provided of the various functions of electrolyte additives, including electrostatic shielding, adsorption, in situ solid electrolyte interphase formation, enhancing water stability, and surface texture regulation. Potential future research directions for electrolyte additives used in aqueous Zn‐ion batteries are also discussed.

Cl-redox reactions cannot be fully exploited in batteries because of the Cl2 gas evolution. Here, reversible high-energy interhalogen reactions are demonstrated by using a iodine-based cathode in combination with a Zn anode and a Cl-containing aqueous electrolyte solution.

Abstract The quest for advanced energy storage devices with cheaper, safer, more resource‐abundant storage has triggered intense research into zinc ion batteries (ZIBs). Among them, organic materials as cathode materials for ZIBs have attracted great interest due to their flexible structure designability, high theoretical capacity, environmental friendliness, and sustainability. Although numerous organic electrode materials have been studied and different redox mechanisms have been proposed in the past decade, their electrochemical performance still needs further improvement, and the mechanisms require further exploration. This paper provides a systematical overview of three types of organic materials (bipolar‐type conductive polymer, n‐type conjugated carbonyl compounds, and p‐type material) on the energy storage mechanisms and distinct characteristics. We then focus on discussing the design strategies to improve electrochemical performance. Furthermore, the challenges and future research directions are discussed to provide a foundation for further developing organic‐based ZIBs.

Because of their high safety, low cost, and high volumetric specific capacity, zinc-ion batteries (ZIBs) are considered promising next-generation energy storage devices, especially given their high potential for large-scale energy storage. Despite these advantages, many problems remain for ZIBs—such as Zn dendrite growth, hydrogen evolution, and Zn anode corrosion—which significantly reduce the coulomb efficiency and reversibility of the battery and limit its cycle lifespan, resulting in much uncertainty in terms of its practical applications. Numerous electrolyte additives have been proposed in recent years to solve the aforementioned problems. This review focuses on electrolyte additives and discusses the different substances employed as additives to overcome the problems by altering the Zn ^2+ solvation structure, creating a protective layer at the anode–electrolyte interface, and modulating the Zn ^2+ distribution to be even and Zn deposition to be uniform. On the basis of the review, the possible research strategies, future directions of electrolyte additive development, and the existing problems to be solved are also described.

The performances of rechargeable batteries are detrimentally affected by low temperatures (e.g., < 0 °C). Here, the authors report a few-layer Bi2Se3 material capable of improving battery cycling performances when operational temperatures are shifted from +25 °C to −20 °C.

Despite the remarkable ion-hosting capability of MXenes, their electrochemical performance is restricted to the ion shuttle barrier stemming from the capacious surface and the sluggish chemical activity of intrinsic transition metal layers. Herein, we construct a vertically aligned array of V2CTX flakes utilizing a carbon sphere template (V2CTX@CS), with the interlayer galleries outward facing the external electrolyte, to shorten the diffusion length and mitigate the ion shuttle barrier. Moreover, we leverage the high sensitivity of V2CTX flakes to the water–oxygen environment, fully activating the masked active sites of transition metal layers in an aqueous environment via continuous electrochemical scanning. Aqueous V2CTX@CS/Zn battery delivers a novel capacity enhancement over 42,000 cycles at 10 A g−1. After activation, the capacity reaches up to 409 mAh [Formula: see text] at 0.5 A g−1 and remains at 122 mAh [Formula: see text] at 18 A g−1. With a 0.95-V voltage plateau, the energy density of 330.4 Wh [Formula: see text] surpasses previous records of aqueous MXene electrodes.

Objectives This study aimed to investigate the differentiation state and clinical significance of colorectal cancer cells, as well as to predict the immune response and prognosis of patients based on differentiation-related genes of colorectal cancer. Introduction Colorectal cancer cells exhibit different differentiation states under the influence of the tumor microenvironment, which determines the cell fates. Methods We combined single-cell sequencing (scRNA-seq) data from The Cancer Genome Atlas source with extensive transcriptome data from the Gene Expression Omnibus database. We obtained colorectal cancer differentiation-related genes using cell trajectory analysis and developed a colorectal cancer differentiation-related gene based molecular typing and prognostic model to predict the immune response and prognosis of patients with colorectal cancer. Results We identified 5 distinct cell differentiation subsets and 620 colorectal cancer differentiation-related genes. Colorectal cancer differentiation-related genes were significantly associated with metabolism, angiogenesis, and immunity. We separated patients into 3 subtypes based on colorectal cancer differentiation-related gene expression in the tumor and found differences among the different subtypes in immune infiltration status, immune checkpoint gene expression, clinicopathological features, and overall survival. Immunotherapeutic interventions involving a highly expressed immune checkpoint blockade may be selectively effective in the corresponding cancer subtypes. We built a risk score prediction model (5-year AUC: .729) consisting of the 4 most important predictors of survival (TIMP1, MMP1, LGALS4, and ITLN1). Finally, we generated and validated a nomogram consisting of the risk score and clinicopathological variables. Conclusion This study highlights the significance of genes involved in cell differentiation for clinical prognosis and immunotherapy in patients and provides prospective therapeutic targets for colorectal cancer.

Obtaining stable aqueous K-ion capacitors is still challenging due to the cathode materials tended to structurally collapse after long-term cycling during large-radius K-ion insertion/extraction. In this work, three different typical MXene electrodes, i.e., Nb2C, Ti2C, and Ti3C2 were individually investigated upon their electrochemical behaviors for potassium-ion (K-ion) storage. All these MXene materials exhibited pseudocapacitive-dominated behaviors, fast kinetics, and durable K-ion storage, delivering superior performance compared with other K-ion host materials. According to the experimental results, it could be ascribed to the intrinsically large interlayer distance for K-ion transport and the superb structural stability of MXene even subjected to long-term potassiation/depotassiation process.

The interactions between water molecules, electrode materials and anions are essential yet challenging for aqueous dual ion batteries. Here, the authors demonstrate the voltage manipulation of dual ion batteries through matching intercalation energy and solvation energy of different anions.

Abstract Rechargeable Zn‐based batteries (RZBs) have attracted much attention and been regarded as one of the most promising candidates for next‐generation energy storage featured with high safety, low costs, environmental friendliness, and satisfactory energy density. The aqueous electrolyte system exhibits great potential to power the future wearable electronics. Apart from the achievements of high capacity cathode and stable electrolyte, the anode suffers from problems of dendrite growth, hydrogen evolution, and passivation with limited attention. The dendrite formation strongly restricts the battery lifespan. Therefore, strategies focused on dendrite suppression are carefully categorized and summarized in this review, including crystallographic orientation manipulation, electric field control, ion flux regulation, and mechanical shield. Each strategy and the detailed approaches are critically dissected. Finally, remaining challenges are emphasized in this review, expecting to supply further research with potential directions to fulfill the high performance of the Zn anodes.

In the past decade, MXenes family have undergone considerable development and have been widely investigated in various research fields, relying on their excellent physicochemical properties. Benefiting from the increasingly versatile preparation methods and the continued discovery of new members, their large-scale application has already been underway, with energy storage fields including supercapacitors and batteries leading. The synthesis methods and processing environment of MXenes, which are closely strictly to the microstructure, surface chemistry, and electronic properties, have attracted great attention. In this review, we review the phylogeny of MXenes materials in recent years, mainly focusing on the synthesis process and environmental stability.

In order to solve the problems of the smooth surface of basalt fiber and its weak interfacial adhesion with emulsified asphalt cold recycled mixture, a silane coupling agent (KH550) was used to treat the surface of basalt fiber and the effects of treatment concentration and soaking time on fiber modification were studied. The influence of silane coupling-modified basalt fiber (MBF) on the rheological properties of emulsified asphalt evaporation residue was studied at high and low temperatures using three routine index tests: a dynamic shear rheological test (DSR), a bending beam rheological test (BBR), and a force ductility test. The elemental changes of the fiber before and after modification and the microstructure of the emulsified asphalt evaporation residue with the coupling-modified fiber were analyzed by Fourier infrared spectroscopy (FT-IR), scanning electron microscopy (SEM), and X-ray energy dispersive spectroscopy (EDS), which is used to study the modification mechanism of emulsified asphalt evaporation residue reinforced by coupling-modified fiber. The results indicate that the concentration and soaking time of the silane coupling agent have a great influence on the surface morphology and mechanical properties of the fiber, and that the optimal treatment concentration is 1.0% and the optimal soaking time is 60 min. The addition of coupling-modified fibers can reduce the phase angle and unrecoverable creep compliance of emulsified asphalt evaporation residue, increase the rutting factor and creep recovery rate, and improve the elastic recovery ability and permanent deformation resistance. However, excessive fiber will weaken the ductility of emulsified asphalt at low temperatures. The appropriate content of silane coupling-modified fiber (MBF) is 1.5%. After silane coupling modification, the fiber surface becomes rough and cohesion is enhanced between the fiber and the emulsified asphalt base. Silane coupling-modified basalt fiber (MBF) acts as reinforcement for stability and bridging cracks.

An urban rail transit (URT) system is operated according to relatively punctual schedule, which is one of the most important constraints for a URT passenger’s travel. Thus, it is the key to estimate passengers’ train choices based on which passenger route choices as well as flow distribution on the URT network can be deduced. In this paper we propose a methodology that can estimate individual passenger’s train choices with real timetable and automatic fare collection (AFC) data. First, we formulate the addressed problem using Manski’s paradigm on modelling choice. Then, an integrated framework for estimating individual passenger’s train choices is developed through a data-driven approach. The approach links each passenger trip to the most feasible train itinerary. Initial case study on Shanghai metro shows that the proposed approach works well and can be further used for deducing other important operational indicators like route choices, passenger flows on section, load factor of train, and so forth.

Recycling phosphogypsum (PG) for cemented paste backfill (CPB) has been widely used at phosphate mines in China. However, the impurities in PG prolong the setting time and reduce the uniaxial compressive strength (UCS), limiting the engineering application of PG. This paper aims to investigate the feasibility of treated PG (TPG) washed repeatedly using deionised water (DW) for CPB. A water-washing pre-experiment was first conducted to find the proportion with the least DW demand and the effects of water-washing on ordinary PG (OPG). Then, based on the PG:DW ratio obtained from the pre-experiment, the properties of the OPG-based CPB (OCPB) and TPG-based CPB (TCPB) were tested using slump tests, UCS tests, and microstructural analysis. The results show that (1) after 11 water-washings at the PG:DW ratio of 1:1.75, the pH of the supernatant (pH = 6.328) meets the requirements of Chinese standard GB 8978-1996. (2) Water-washing improves the particle gradation quality of PG and removes the soluble impurities adsorbed at the surface of PG crystals. (3) The initial slump values of TCPB are 0.19–1.15 cm higher than that of OCPB, furthermore, the diffusivity values of TCPB are better than the performance of OCPB, with 0.61–1.68 cm of superiority. (4) The UCS values of TCPB are up to 0.838 MPa, 1.953 MPa, and 2.531 MPa, after curing for 7, 14, and 28 days. These are 0.283 MPa, 0.823 MPa, and 0.881 MPa higher than that of OCPB, respectively. It can be concluded that water-washing pre-treatment greatly improves the workability and mechanical property of PG-based CPB. These results are of great value for creating a reliable and environmentally superior alternative for the recycling of PG and for safer mining production.

Theoretically speaking, the data of a stated preference survey could be suggested for the calibration of a stochastic route choice model. However, it is unrealistic to implement the questionnaire survey for such a large number of alternative routes. Engineers generally determine the parameter empirically. This experienced choice of perception parameter may cause higher errors in the route flows. In our calibration model of the perception parameter, the data of the cellular network is set as the input. This model consists of two levels. The upper level is to minimize the gap squares of the route choice ratio between the C-logit model and the cellular network data. The stochastic user equilibrium (SUE) in terms of the C-logit model is used as the lower level. The simulated annealing (SA) algorithm is used to solve the model, where the route-based gradient projection (GP) algorithm is used to solve the inner SUE. A case study is used to validate the convergence of the model calibration. A real-world road network is used to demonstrate the objective advantage of an equilibrium constraint over a nonequilibrium constraint and explain the feasibility of the candidate routes assumption.

The security and reliability of rail transit vehicles in service are greatly affected by their wheel-rail contact. Thus, modeling the wear of wheelsets and monitoring their status is important for improving safety and reducing costs. A key issue involves evaluating the wheelset status accurately and using this as the basis for developing effective maintenance strategies and measures. However, the open nature of actual wheel-rail systems and their inconsistent environmental conditions make it difficult to construct a precise theoretical model that covers both wheelset wear and status evaluation. In this paper, a synthesis approach for evaluating the wheelset health status of rail transit vehicles is proposed. The wheelset health status is defined, and then a data-driven wheelset health evaluation model is developed. Potential causes of deviations between the model and reality are analyzed based on a theoretical wear mechanism, and application prerequisites for the proposed model are given. A case study involving the Shanghai Metro shows that the proposed approach operates well and can, therefore, be applied in practice. [ABSTRACT FROM AUTHOR]

High specific capacity and long cycling life of anode materials still remain major challenges in the development of sodium-ion batteries (SIBs). Nowadays, transition metal phosphides have been reckoned as promising anodes in view of their high theoretical specific capacities, low potential for sodium storage, and superior conductivity. Herein, molybdenum phosphide (MoP) nanorods wrapped with thin carbon layer have been prepared and applied as an anode for SIBs. By utilizing in situ X-ray diffraction technology, a conversion-type mechanism of MoP anode has been disclosed. This kind of MoP electrode exhibits extraordinary electrochemical properties, including excellent cycling performance with a discharge capacity of 398.4 mA h g-1 at a current density of 100 mA g-1 after 800 cycles, and remarkable rate capabilities, which remain 104.5 mA g-1 at 1600 mA h g-1 even after 10 000 loops. The distinguished performances stem from synergetic merits of the morphology, structure, and mechanism of MoP. It is expected that MoP will be a promising anode material for SIBs and this work would provide theoretical basis for the scalable research and applications of MoP-based anode materials for SIBs. [ABSTRACT FROM AUTHOR]

The superior low-cost porous carbon (SLPC) with an expanded interlayer spacing of 0.39 nm and a high surface area of ~685 m2 g-1 was obtained by a direct pyrolysis of dried camphor wood without additional activation. Benefiting from the expanded interlayer spacing and high surface area, the obtained carbon exhibited an excellent electrochemical sodium ion storage performance with a high reversible capacity of ~310 mAh g-1 after 100 cycles between 3.0 and 0.01 V (vs Na+/Na) at a constant current density of ~0.1 A g-1. More importantly, an excellent rate capability of ~120.6 mAh g-1 after 5000 cycles was delivered at a rather high current density of 5 A g-1, which is almost the best among the biomass-derived carbon anodes. The excellent performance of SLPC for SIBs may be attributed to the fast capacitance behavior and rapid mass transfer process profiting from porous structure of the carbon existing in biological tissue. Considering the superior low cost and excellent electrochemical sodium storage performance of SLPC, the SLPC might be a highly promising anode material for the practical application of SIBs. [ABSTRACT FROM AUTHOR]

The anatase TiO2 nanodots/carbon composites were prepared by an in-situ grown method induced by 3D porous carbon. Compared with the pure TiO2, the hybrid material of anatase TiO2 nanodots/carbon composites (denoted as AT@3DC) exhibited a smaller particle size with a diameter range from 5 nm to 10 nm and better electronical conductivity. When utilized as anode material for sodium-ion batteries (SIBs), the AT@3DC electrode showed ultrahigh cycling performance and ultrafast charge/discharge performance. A reversible sodium-ion storage capacity of ~235.5 mAh g-1 is maintained after 200 cycles at 0.5 C-rate, and ~112.8 mAh g-1 could be obtained at 20 C-rate after 5000 cycles with almost no decay, which indicate the high stability of the AT@3DC. The excellent rate capacity and ultralong cycling life are attributed to the unique 3D porous carbon support, which can assist the nucleation of Ti(OH) 2C2O4 and limit their growth, effectually inhibit the aggregation of titanium dioxide nanodots, enhance the charge transfer rate and increase the mass transfer rate of Na+. Considering the excellent Na+ storage performance and ultrahigh cycling stability, the AT@3DC might be a promising anode material for the SIBs in the future. [ABSTRACT FROM AUTHOR]