Despite the promising sodium-storage characteristics of NASICON-type Na3MnTi(PO4)(3) arising from its stable three-dimensional framework and high ionic conductivity, its practical performance remains limited by the low Ti3+/Ti4+ redox potential, poor electronic conductivity, and Mn3+-induced Jahn-Teller distortion. In this study, Na3MnTi1-xNbx(PO4)(3) (x = 0, 0.025, 0.05, 0.075, 0.1) was synthesized via a sol-gel method. X-ray diffraction confirms that Nb5+ substitution at Ti sites preserves the NASICON structure while slightly expanding the lattice and promoting Na+ transport. Electrochemical tests show that appropriate Nb doping not only increases the high-voltage capacity corresponding to the Mn2+-> Mn4+ redox process, but also improves the rate capability, cycling stability, and reversibility of Na3MnTi1-xNbx(PO4)(3) cathodes. The Na3Ti0.95Nb0.05Mn(PO4)(3) sample delivered an initial capacity of 139.0 mAh g(-1) and maintained 74.1 mAh g(-1) after 500 cycles at 180 mA g(-1). Moreover, it exhibits enhanced rate capability, maintaining 88.6 mAh g(-1) as the current density increases to 900 mA g(-1). These findings indicate that Nb-doping is an effective strategy to enhance the electrochemical performance and structural stability of Na3MnTi(PO4)(3).

Manganese slag production has become a critical problem due to the increasing demand for manganese ore in lithium-ion battery cathode materials, posing serious resource and environmental concerns. The effective recovery of residual Mn/Fe is frequently limited by conventional separation techniques including flotation, magnetic separation, and gravity separation, which have either low extraction rates or high operating costs. To address this issue, herein, this work proposes a unique hydrocyclone separation-leaching collaboration approach via using the Unreacted Shrinking Core Model (USCM) with Computational Fluid Dynamics (CFD) simulations for the first time. According to simulated and experimental results, the procedure can achieve an excellent 99.84% separation efficiency of Fe2O3 to the underflow, while also attaining reaction rates of 78.27% for MnO and 15.44% for Fe2O3. This innovation not only validates the feasibility of simultaneous leaching and separation but also expands the application scope of hydrocyclones from traditional separation to reaction kinetics, offering a sustainable and eco-friendly solution for manganese slag recycling.

The construction of heterostructures is a promising strategy to enhance charge transfer efficiency in electrode materials, however, achieving precise control over interfacial interactions within two-dimensional lamellar hosts remains challenging. Siloxene with two-dimensional lamellar structure was synthesized via the topological transformation of calcium disilicide precursor. Ni3S4 nanoparticles were then anchored between the interlayers of siloxene skeleton through the solvothermal method. The effect of solvothermal time on the morphology and electrical properties of Ni3S4/siloxene composite was investigated in detail. The composite obtained with the optimal solvothermal time of 9 h (NS-9) effectively inhibits the restacking of siloxene layers, thereby facilitating electron and ion transport and providing a larger contact area and more active sites for redox reactions. The synergistic effect between Ni3S4 and siloxene enhances the electron density within the heterostructure and significantly enhances the electron transfer efficiency compared to the individual components. The resulting Ni3S4/siloxene electrode displays outstanding electrochemical performance, achieving a specific capacitance of 1090 F g-1 at the current density of 0.5 A g-1. Additionally, the assembled NS-9//AC asymmetric supercapacitor delivers 37.1 Wh kg-1 energy density at the power density of 801.1 W kg-1. Therefore, the Ni3S4/siloxene heterostructure is demonstrated to be a promising electrode material for advanced energy storage applications.

Single-crystal ternary cathode materials are regarded as promising next-generation cathode materials for lithium-ion batteries due to their excellent cycling performance and high safety. However, the industrial-scale production of single-crystal NCM continues to pose significant challenges, primarily attributable to complex processing routes and high manufacturing costs. In this work, the electrochemical behavior of NCM cathodes is explored in relation to the varying temperatures at which metal-organic framework (MOF) precursors are prepared. The MOFs were synthesized using nickel-cobalt-manganese acetates and terephthalic acid as starting materials. The MOF-derived precursors exhibit high reactivity, enabling the synthesis of single-crystal NCM811 via conventional solid-state sintering. The results reveal that increasing the preparation temperature of the Ni/Co/Mn-based MOF precursor leads to a progressive increase in Li/Ni cation disorder within the resultant NCM cathode material. Among the samples, MOF-NCM-0, prepared at 0 degrees C and derived from Ni/Co/Mn-MOF precursors via sintering, exhibits the most favorable electrochemical performance. Compared with the commercial polycrystalline cathode material (PC-NCM), the single-crystal MOF-NCM-0 synthesized in this study demonstrates superior properties, including enhanced capacity retention, lower activation energy for lithium-ion diffusion, and higher compressive strength. A novel strategy for the preparation of high-performance monocrystalline NCM811 cathode materials is proposed in this work.

Lithium-ion batteries have prompted a substantial wave of decommissioning activity, and research into the recycling processes for these batteries has progressed rapidly both domestically and internationally. Nonetheless, there exists a scarcity of studies examining the ecological effects linked to various recycling methodologies. This paper assesses the environmental implications of recovering regenerated lithium ternary batteries (NCMs) through an acetic acid-hydrogen peroxide leaching system at a laboratory scale, employing the Life Cycle Assessment framework with the aid of SimaPro software. The environmental footprint of the process was quantitatively assessed utilizing the IMPACT 2002+ methodology. The results demonstrate that fossil energy consumption is the predominant factor during the production stage of NCM cathode materials. Conversely, the environmental effects during the end-of-life recycling stage are primarily attributable to electrical energy consumption. A key innovation of this work lies in the integration of laboratory-scale experimental data with LCA modeling, enabling sensitivity and uncertainty analyses that enhance the predictive accuracy of environmental impacts prior to industrial deployment. This approach not only bridges the gap between laboratory research and industrial application but also provides strategic insights for optimizing process design, reducing ecological burdens, and advancing sustainable large-scale recycling pathways for lithium-ion batteries.

Sodium-ion batteries (SIBs) are promising for grid-scale energy storage due to sodium's abundance and low cost. Petroleum-derived pitch-based hard carbon (HC), a value-added product from chemical industry byproducts, is a cost-effective anode candidate, yet its inherent graphitization leads to insufficient active sites and sluggish kinetics, while uncontrolled heteroatom doping often introduces detrimental "trap effects." that cause irreversible capacity loss. Herein, we develop a synergistic template-preoxidation and gradient N/P co-doping strategy to precisely tailor the carbon structure and balance active sites with trap effects. The optimized C-NP(7:3) exhibits an expanded interlayer spacing (0.388 nm), abundant active sites (pyridinic/pyrrolic N, P=O/P-C), and consequently delivers a high reversible capacity (409 mAh g-1 at 0.1 C) with exceptional cycling stability (89.48% retention after 1000 cycles at 2 C) and superior rate capability (116.56 mAh g-1 at 6 C). Kinetic analyses reveal enhanced Na+ diffusion and dominant capacitive storage, collectively explaining the superior performance. Density functional theory (DFT) calculations confirm the N-P co-doped configuration's optimal Na+ adsorption energy (-95.89 kcal/mol), which achieves the delicate balance of active site-trap effect and provides a dual-driven design approach for high-performance HC. This work provides mechanistic insights into the rational design of heteroatom-doped petroleum-derived carbon anodes via chemical modification for efficient energy storage.

Single-crystal layered oxides represent a frontier in the development of electrode materials for high-energy lithium-ion batteries (LiBs), achieving extended lifetimes by avoiding structural reconstruction and mechanical collapse caused by cracks, unlike polycrystalline materials. However, current preparation methods for single-crystal materials rely on specialized process routes, and challenges such as complex production workflows, substantial manufacturing costs, and quality consistency hinder large-scale commercialization. Therefore, this study proposes an innovative strategy for synthesizing single-crystal ternary cathode material NCM811 through a simplified approach. The thickener-assisted gel synthesis method successfully produced high-performance single-crystal high-nickel ternary cathode materials across different systems (CMC/ALG/KGM). The ALG system demonstrated the most optimal performance among the single-crystal high-nickel ternary cathode materials, achieving a discharge capacity of 176.98 mAh/g under 1C discharge conditions. Cross-sectional SEM images reveal that after 200 cycles, the ALG-NCM material synthesized via the ALG system maintains its initial structural integrity without significant intragranular microcracks. The selected thickener in this method is inexpensive, environmentally friendly, readily available, and the preparation process is straightforward. This study underscores the significant practical importance of simple preparation methods for the industrial production of single-crystal high-nickel cathode materials.

The NiCoLDH/Ni-Co-S heterostructured composite was synthesized as a supercapacitor electrode via a two-step electrodeposition method. The effects of the electrodeposition cycles on the morphology and electrochemical properties of the NiCoLDH/Ni-Co-S electrode were investigated. Using NiCoLDH as a structural scaffold, Ni-Co-S was deposited on the NiCoLDH arrays to form a unique three-dimensional nanoflower architecture. The synergistic effect between Ni-Co-S and NiCoLDH significantly enhances the surface electroactive sites, leading to improved electrochemical performance. As a result, the optimized NiCoLDH/Ni-Co-S-8 electrode demonstrates a specific capacitance of 10.85 F cm- 2 at 1 mA cm- 2, while maintaining 85% capacitance retention even with a 20fold increase in current density. Furthermore, the assembled NiCoLDH/Ni-Co-S-8//AC asymmetric supercapacitor achieves a power density of 800 mu W cm- 2 and an energy density up to 1060 mu Wh cm- 2. This work provides a novel modification strategy to improve the electrochemical properties of LDH-based composites.

Spent lithium-ion batteries pose environmental risks and resource depletion, with separating cathodes active materials from Al foil being the critical step for recycling. Furthermore, its efficiency directly impacts the performance of subsequent recycling steps. Herein, a separation method based on a chelation mechanism for recovering LiFePO4 (LFP) is proposed. This approach differs fundamentally from conventional separation techniques. Ethylenediaminetetraacetic acid (EDTA) reacts with metallic aluminum and the surface Al2O3 layer on aluminum foil. As a result, the interfacial interaction between LFP and aluminum foil is disrupted. A separation efficiency of 99.9% of LFP is achieved, with highly preserved crystal structure of LFP. Meanwhile, a dense AlEDTA passivation layer forms on Al foil to prevent further corrosion, and EDTA features minimal single-use consumption and reusability. The separated LFP was directly regenerated via a molten-salt method, and the regenerated product exhibited excellent electrochemical performance. Life cycle assessment and technoeconomic analysis further indicate its potential to promote the sustainable and economically viable development of the spent battery recycling industry.

To achieve large-scale application of solvothermal method and settle structural collapse of polycrystalline ternary NCM cathode materials (LiNi0.8Co0.1Mn0.1O2, NCM811) during long charge and discharge cycling, single-crystalline NCM materials with high cycling stability were prepared by rapid ethanol-water solvothermal method. The morphology and electrochemical properties of NCM materials were characterized by X-ray diffractometry, cross-section scanning electron microscopy, transmission electron microscopy, X-ray photoelectron spectroscopy, and electrochemical measurement. The results show that single-crystalline NCM synthesized with 60 min solvothermal time has the most excellent electrochemical performance. Its reversible capacity reaches 157.28 mA & centerdot;h/g at 1C and retention rate achieves 55.06% after 200 cycles, which is much better than the polycrystalline NCM cathode material. Cross-section scanning electron microscopy results show that the single-crystalline NCM cathode material has no apparent cracks after 200 cycles.

The tendency toward developing new technologies for the comprehensive exploitation of diverse elements found in minerals is unavoidable given the growing scarcity of resources and the growing prominence of environmental issues. Low-temperature calcined laterite nickel ore is an essential raw material supply channel for battery grade nickel sulfate in the renewable energy era, playing a major part in the nickel industrial chain. In this research, laterite nickel ore was chosen as an initial ingredient to produce filtrate with a high nickel concentration through leaching and directed impurity removal, and rare earth element La was utilized to substitute partial Mn in the transition metal layer. A series of stacked hexagonal plate P2-Na0.67Ni0.33Mn0.67- xLaxO2(x = 0, 1/48, 1/24, 1/ 12) materials (designated NNMLx) were synthesized via the coprecipitate method. The findings demonstrate the outstanding sodium storage ability of NNML1/24, with an initial discharge capacity of 148.73 mAh/g at 0.1 C and a potential range of 2.0-4.3 V. It also boasts superb rate performance (129.76 mAh/g at 10 C) and a high level of cycle stability (91.50 % capacity after 200 cycles). Consequently, the layered structure may be stabilized, phase change can be inhibited, and interlayer slip can be efficiently reduced by adding La.

To address the issue of agglomeration and partial oxidation of transition metal sulfides (TMSs) in supercapacitor applications, this study successfully constructed a three-dimensional heterogeneous composite material with a hierarchical structure of MoS2-Ni3S4/Siloxene on two-dimensional layered siloxene via a facile one-step solvothermal method. MoS2 acts as both a stabilizer and a conductive bridge, inhibiting the partial oxidation of sulfides and establishing a strong interfacial chemical interaction. Thanks to the multi-component synergistic effects between siloxene and transition metal sulfides, coupled with the three-dimensional structure, the composite facilitates rapid electron/ion transfer and suppresses the agglomeration and re-stacking of nanoparticles. The resulting MoS2-Ni3S4/Siloxene electrode delivers outstanding electrochemical performance, exhibiting a high specific capacitance of 1365 F g- 1 at 0.5 A g- 1 and maintaining 73.2 % capacitance retention after 4000 cycles. Moreover, it exhibits excellent rate capability, retaining 58.2 % of its initial capacitance at a high current density of 10 A g- 1. The assembled MNS-180//AC asymmetric supercapacitor exhibits a maximum energy density of 41.8 Wh kg- 1 at a power density of 800.3 W kg- 1 and maintains 28.69 Wh kg-1 at a high power density of 7824.5 W kg- 1. The device also displays extraordinary cycling durability with 85.3 % capacitance retention after 4000 cycles. This work demonstrates the effectiveness of enhancing electrode performance through the synergistic effects of MoS2, Ni3S4, and siloxene, and offers a promising approach for developing highperformance energy storage systems.

Antimony-based materials, which have high capacities and moderate potentials, are seen as promising anode candidates for sodium-/potassium-ion batteries. However, they suffer from huge volume expansion and poor conductivity, leading to low structural stability and slow reaction kinetics. In this manuscript, 2D MXene nanosheets was firstly prepared as the supported substrate through HF free etching strategy of Ti3AlC2 bulk material. Then the final product of MXene@Sb/In2S3 heterostructure was synthesized by solvothermal method and the subsequent low temperature annealing process. The abundant oxygen-containing groups on the surface of MXene provide abundant nucleation sites for the homogeneous anchoring Sb3+/In3+and growth of Sb/In2S3 nanocrystals. Furthermore, the MXene@Sb/In2S3 heterostructure, with dispersed Sb/In2S3 nanocrystals on the MXene surface, greatly mitigate MXene nanosheet restacking, thereby exposing more active sites to the electrolyte. When used as the electrode materials for Na+/K+ batteries (SIBs /PIBs), MXene@Sb/In2S3 heterostructure presents excellent electrochemical and battery performance. In SIBs, it holds the capacity of 320mAh g-1 at a current density of 1 A g-1 1000 cycles. In PIBs, MXene@Sb/In2S3 showed rate performance comparable to other reported potassium-electric materials of the same type and retained A reversible capacity of 185mAh g-1 after 650 cycles at a constant current of 1 A g-1. This design strategy provides a valuable guidance for the development of high-performance alloy-based and conversion-type anodes for energy storage devices.

Solid-state sodium batteries present a high potential for future energy technology due to their high safety and energy density. However, sluggish Na+ transportation of solid-state electrolytes and serious Na dendrites hinder their further development. Herein, we propose a negatively charged-modified covalent organic framework (COF) with -SO3Na as a Na-ion quasi-solid-state electrolyte (QSSE-COF-SO3Na) for the first time to enhance the Na+ transportation. Density functional theory calculations and molecular dynamics simulations prove that the nanoscale ion channels of the COF-SO3Na and the interaction between the -SO3- and the anion PF6- effectively enhance the Na+ diffusion kinetics. The QSSE-COF-SO3Na exhibits a high ionic conductivity of 4.1 x 10-4 S cm-1 at room temperature and a high transference number of 0.89. Particularly, Na|QSSE-COF-SO3Na|Na symmetric cells show a stable Na plating/stripping process without Na dendrites over 1000 h and 800 h at 0.05 and 0.2 mA cm-2, respectively. Additionally, the QSSE-COF-SO3Na supports full cells, which respectively use NaTi2(PO4)3, Na3V2(PO4)3, and NaFePO4 as cathodes, to display good cycling stability and rate performance. This work highlights the novel strategy to develop the Na-ion quasi-solid-state devices.

The two-dimensional (2D) layered structure material was prepared by etching the precursor CaSi2 with topological transformation. The effects of different drying methods on the morphological structure, elemental composition and electrochemical properties of siloxene samples were investigated. The results showed that the siloxene materials prepared by supercritical drying have the largest specific surface area and fast ion diffusion rate due to the reduction of interlayer stacking and aggregation. The supercritical drying protected the backbone structure of siloxene, resulting in better electrochemical properties. Siloxene-S has a specific capacitance value of 134 F g−1 when the current density is 0.5 A g−1. When the current density was increased to 4 A g−1, the specific capacitance of Siloxene-S remained 96 F g−1. The assembled Siloxene-S//AC device provided a maximum energy density of 5.89 Wh kg−1 at a power density of 209.8W kg−1, which confirmed that siloxene has broad application prospects as electrochemical energy storage material.

Laser‐directed energy deposition (LDED) additive manufacturing presents significant advantages for fabricating laminated materials with enhanced mechanical properties. This study investigates the in situ synthesis of TiN/TC4 laminated materials, developed using different layering strategies in the LDED process under alternating atmospheres of pure argon and nitrogen–argon gas mixtures. The effects of these layering strategies on the microstructure and mechanical properties of the synthesized materials are systematically analyzed. As the proportion of in situ synthesized layers increases, significant microstructural evolution is observed: the average grain size increases, the structure transitions from a Widmanstätten pattern to a basketweave structure, and the grain morphology shifts from columnar to equiaxed crystals. Correspondingly, the elongation at fracture decreases, while tensile strength initially increases and then declines. Notably, the 2‐1 layering strategy achieves a peak tensile strength of 1135.0 ± 26.8 MPa, reflecting a 21.6% improvement compared to titanium alloy samples fabricated in a pure argon atmosphere. This study highlights the versatility of combining LDED with controlled deposition atmospheres to enable the tailored synthesis of laminated materials. The ability to manipulate microstructure and mechanical properties through specific layering strategies offers significant potential for advancing the development and application of high‐performance laminated materials.

The urgent demand from society for lithium-ion batteries necessitates the research of high-performance and high-stability cathode materials. Although the high nickel material has a high theoretical capacity, its stability has hindered the commercialization progress. In this work, we propose a new strategy guided by theory. By doping NCM622 with rare earth elements that possess high-energy d-level and f-level electrons and high charge density, it is theoretically possible to contribute more electronic states near the Fermi level, thereby enhancing the internal electronic conductivity of the material. This strategy not only increases the energy density but also inhibits the Li/Ni mixing and improves the cycle stability of the battery. The 1/24 Dy-doped NCM622 exhibits metallic conductors in both R_3m and monoclinic C2/m space groups, and thus has better electrical conductivity. The results of XRD refinement show that the Li/Ni mixture is effectively inhibited. Electrochemical data confirmed that the material can reach the ultra-high capacity of 210.8 mAh g-1 at 0.1 C, and can still have 87.1 % energy residual after 300 cycles. The excellent electrochemical performance also depends on the synthesis optimization of the pure phase materials that we have explored using the orthogonal method. This study provides theoretical guidance for the application of rare-earth elements in high-nickel materials.

O3-type layered oxides that are of the type of O3 serve as attractive cathode materials for sodium-ion batteries due to their facile production and elevated sodium content. Nonetheless, their practical application is impeded by intricate phase transitions and inadequate air stability. This paper presents a sodium alginate sol-gel approach that utilizes sodium alginate as both a sodium supply and a chelating agent. This method creates a 3D mesh structure through the binding of transition metal salts, facilitating the synthesis of O3-type high-entropy layered oxides. The high-entropy design improves the reversibility of the O3-P3 phase transition, inhibits Na+/H+ exchange to decrease air reactivity, and stabilizes the material's structure, thus minimizing electrochemical deterioration during cycling. DFT calculations demonstrate that the increased Li elements in the high-entropy oxides Na0.9Ca0.05Fe0.2Mn0.2Ni0.2Ti0.2LixCo0.2-xO2 increase the local bonding strengths of TM-O near the Li doping sites and improve the structural stability. The optimized cathode preserves 71% capacity after 200 cycles at 10 C (starting capacity: 117 mAh g-1) and sustains 115 mAh g-1 for 100 cycles at 1 C (85.2% retention) after 10 days of exposure to air with 40-50% relative humidity. This study promotes a high-entropy approach for the development of high-performance, air-stable O3-type cathodes for sodium-ion batteries.

CuCrZr/GH4169 multi-material structures combine the high thermal conductivity of copper alloys with the high strength of nickel-based superalloys, making them suitable for aerospace components that require efficient heat dissipation and high strength. However, additive manufacturing of such dissimilar metals faces challenges, with each laser powder bed fusion (LPBF) and laser directed energy deposition (LDED) process having its limitations. This study employed an LPBF-LDED integrated additive manufacturing (LLIAM) approach to fabricate CuCrZr/GH4169 components. CuCrZr segments were first produced by LPBF, followed by LDED deposition of GH4169 layers using optimized laser parameters. The microstructure, composition, and mechanical properties of the fabricated components were analyzed. Results show a sound metallurgical bond at the CuCrZr/GH4169 interface with minimal porosity and cracks (typical defects at the interface), achieved by exceeding a threshold laser energy density. Elemental interdiffusion forms a 100-200 μm transition zone, with a smooth hardness gradient (97 HV0.2 to 240 HV0.2). Optimized specimens exhibit tensile failure in the CuCrZr region (234 MPa), confirming robust interfacial bonding. These findings demonstrate LLIAM's feasibility for CuCrZr/GH4169 and underscore the importance of balancing thermal conductivity and mechanical strength in multi-material components. These findings provide guidance for manufacturing aerospace components with both high thermal conductivity and high strength.

Metals with high thermal and electrical conductivity, such as copper, have limited tensile strength, which restricts their broad application in industry. The integration of functional and structural components can be achieved through the design and fabrication of multi-material structures. This study investigates the mechanical and physical properties of copper-stainless steel (Cu-SS) multi-material structures fabricated using blue laser directed energy deposition (BL-DED) technology. By optimizing process parameters, high relative densities of Cu and SS were achieved. The performance differences of Cu-SS multi-materials under various Cu-to-SS ratios were revealed through comprehensive analysis of the interfacial microstructure, elemental distribution, as well as thermal conductivity, electrical conductivity, and mechanical properties. The results indicate that as the content of SS decreases, the thermal conductivity of the Cu-SS structures is significantly enhanced, while the mechanical properties are notably reduced. Due to the substantial difference in electrical conductivity between Cu and SS, the eddy current electrical conductivity exhibits distinct measurement-side-dependence. Furthermore, a balance relationship for the performance of Cu-SS multi-material structures has been established through theoretical modeling and experimental validation, providing an optimization framework for achieving high thermal conductivity, high electrical conductivity, and high strength in multi-material structures. This study offers new insights into the design and fabrication of functional and structural integration in advanced engineering components.