Rare Metals最新文献

Electrodeposition activation of metal–organic frameworks (MOFs) has emerged as a promising strategy for the synthesis of highly efficient electrocatalysts for oxygen evolution reaction (OER). Herein, a cathodic electrodeposition method is presented to activate NiFe-based MOF nanosheets on a nickel foam (NF) support to form a NiFe-MOF/(oxy)hydroxide nanocomposite (A-NiFe-TDC). This activation route not only creates abundant defective structures but also involves partial valency reduction in Ni/Fe species and electron transfer to grow a new component of NiFe-(oxy)hydroxide on the surface of the NiFe-TDC MOF. By adjusting electrodeposition times and Ni/Fe mol ratios, the as-prepared A-NiFe-TDC-5 nanocomposite exhibits improved electrocatalytic performance for OER in an alkaline medium, achieving a high current density of 100 mA cm⁻² at a low overpotential of 242.9 mV, a small Tafel slope of 24.9 mV dec⁻¹, and good long-term stability over 450 h. After OER, A-NiFe-TDC-5 is self-reconstructed to form NiFe-OOH nanosheets, contributing to optimizing the electronic structures and further improving the electrocatalytic activity and stability. This work provides a viable and effective electrodeposition activation method for the preparation of MOF-based nanocomposites to boost the electrocatalytic performance for OER.

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TiNb₂O₇ (TNO) is regarded as a potential fast-charging anode for lithium-ion batteries due to its fast reversible phase transition and safe working potential, but it suffers from unsatisfactory electronic conductivity, sluggish ion kinetics, and poor structural stability under high rates. Herein, tantalum (Ta) with strong Ta–O bonds is doped into TNO to enhance its fast-charging property and structural stability. Proper amount of Ta doping not only increases the interlayer spacing for fast Li⁺ transport, but also improves the electrical conductivity, being successfully proved by experimental analyses. Density functional theory (DFT) calculation verifies that the lattice distortion induced by the incorporation of strong Ta-O bonds can effectively strengthen the structural stability. Notably, in situ X-ray diffraction (XRD) technology reveals that Ta doping relieves volumetric strain during lithiation and de-lithiation. Thus, the optimized Ta_0.1-TNO sample owns impressive long-term cycling stability even at a high current density of 10C, which delivers a high-capacity retention of 85.12% (a capacity decay of less than 0.01% per cycle) after 1500 cycles. This work provides a fast-charging anode material with superior structural stability for lithium-ion batteries.

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Micro-nanostructured materials exhibit unique physical and chemical properties, making them valuable for both scientific research and technological applications. Particularly, these materials significantly improve the electrochemical performance of lithium-ion batteries (LIBs). Spray drying (SD), a facile and scalable synthesis method, provides an effective strategy for the precise design and fabrication of functional nanostructured materials with tailored compositions and morphologies. This review provides a comprehensive overview of recent advances in the application of SD for fabricating key micro-nanomaterials for LIBs. The paper examines the fundamental principles of SD, its historical development in the LIB field, and its current industrial status. The review systematically evaluates strategies for applying SD to enhance the performance of typical LIB cathode and anode materials. Additionally, the inherent advantages and current challenges of SD are comprehensively analyzed. This paper provides valuable theoretical and practical guidance for the advancement of SD in the fabrication of high-performance micro-nanostructured materials for LIBs.

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Ammonia is regarded as “Hydrogen 2.0” and is an ideal zero-carbon energy source. Electrocatalysis technology enables the synthesis of ammonia at room temperature and pressure. Iron-based catalysts exhibit great potential in electrocatalytic ammonia synthesis because of the unfilled d-orbital of iron sites, which are beneficial for the adsorption and activation of reactive species. This review unveils cutting-edge developments of iron-based catalysts in electrocatalytic ammonia synthesis. Firstly, the fundamental principle of electrocatalytic ammonia synthesis is introduced. The nanostructure-catalytic activity relationship, the electronic structure-catalytic activity relationship, and the influence of electrolyte properties on catalytic performance are also analyzed to work out the key parameters for designing efficient iron-based catalysts and electrodes. Lastly, the challenges and development prospects of iron-based catalysts for electrocatalytic ammonia synthesis are highlighted to guide the development of low-cost and large-scale sustainable electrocatalysts.

The Ga-doped Li₇La₃Zr₂O₁₂ (Ga-LLZO) system currently exhibits the highest ionic conductivity among garnet-type solid-state electrolytes and faces persistent challenges including pore formation—arising from high-temperature disproportionation reactions and elevated sintering activity—as well as lithium filament growth and short-circuit failure at pores and grain boundaries. Effectively addressing these issues while retaining high ionic conductivity remains a major obstacle. In this study, Ce was introduced into the Ga-LLZO lattice via an in situ tuning strategy, which significantly reduced internal pore retention and suppressed the reduction of migrating Li⁺ into dead lithium. The optimized Ce in situ tuning controlled Ga-LLZO achieved an ionic conductivity exceeding 1 mS cm⁻¹ at 25 °C, while the critical current density (CCD) in lithium symmetric cells reached 0.7 mA cm⁻²—twice that of unmodified Ga-LLZO. Remarkably, no short-circuiting occurred even after 2700 h of cycling at 0.3 mA cm⁻², in contrast to the unmodified Ga-LLZO, which failed after only 50 h. The corresponding full cells also demonstrated excellent cycling stability and ultra-high capacity retention, significantly outperforming unmodified Ga-LLZO. Compared with recent electrolyte modification strategies, the Ce in situ tuning controlled Ga-LLZO delivers outstanding overall performance. Moreover, it holds strong potential for synergistic integration with other advanced modification techniques, offering broad prospects for further development and practical implementation in next-generation all-solid-state batteries (ASSBs).

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Lithium-ion batteries (LIBs) are highly efficient devices for secondary energy and conversion. Prelithiation is emerging as a promising strategy for developing next-generation high-performance LIBs, with rapid advancements achieved through various innovative methods. This review summarizes prelithiation strategies from a new original perspective, which is based on the utilization of lithium metal, lithium-containing compounds, and introduced prelithiation methods without any additional lithium sources firstly. Furthermore, the industrialization progress of various prelithiation methods is presented. Based on key industrialization criteria, the merits and limitations of various prelithiation strategies have been comprehensively assessed, along with a discussion of their future challenges and perspectives facing its industrialization. Key internal mechanisms of prelithiation are described, including electron pathway density in contact prelithiation and the intrinsic influence of electrode damage in mechanical prelithiation. Additionally, evaluation methods and theoretical models for prelithiation are presented. The comprehensive effects of prelithiation on electrochemical performances are analyzed, offering valuable insights into its benefits and limitations. Finally, the extended applications of prelithiation, including its potential in battery recycling processes, solutions to critical challenges in lithium-sulfur batteries (LSBs) and lithium-oxygen (Li-O₂) batteries, and its inspired adaptations for sodium-ion (SIBs) and potassium-ion batteries (PIBs), are systematically highlighted in this review.

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Designing magnetic van der Waals (vdW) heterostructures by stacking two-dimensional (2D) magnetic materials with other 2D materials enables the investigation of 2D spintronics owing to the strong magnetic proximity effect. Spin manipulation at the vdW interface can be achieved by stacking architectures and external stimuli, such as magnetic fields, electric fields, stress, and light. Moreover, elucidating the effects of magnetic interfacial interactions and related interlayer coupling is crucial for exploring practical spintronic applications of magnetic vdW heterostructures. In this review, vdW interlayer interactions are categorized into spin–orbit coupling, spin transfer torque, and spin–charge transfer, and the magnetic vdW heterostructures are classified into three categories: magnetic material/magnetic material, magnetic material/non-magnetic material, and magnetic material/ferroelectric material heterostructures. Subsequently, related interfacial interactions in magnetic vdW heterostructures are introduced, and the spin manipulation technique is discussed. Moreover, various applications of magnetic vdW heterostructures by modulating the electron spin are explored. Finally, emerging opportunities are highlighted, and a perspective on the future development of magnetic vdW heterostructures through delicate spin manipulation is provided.

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Magnetic vdW heterostructures are classified according to vdW interlayer interactions including spin-orbit coupling, spin-transfer torque, and spin-charge transfer. Various applications and perspectives of magnetic vdW heterostructures allow authors to explore novel applications through spin manipulation.

Red phosphorus (RP), one high theoretical specific capacity (2596 mAh g⁻¹) anode material, suffers from severe volume expansion and ion transport lag during charge and discharge process. Herein, barium titanate (BTO) nanoparticles with spontaneous polarization effect are introduced into RP-based composites to suppress the volume expansion of RP and accelerate the bulk charge transfer. In situ X-ray diffraction technology and Kelvin probe force microscopy synergistically clarify the stress applied to BTO during the RP alloying reaction can effectively increase the dipole moment of BTO, thereby increasing the ion diffusion coefficient of RP-based anode material by approximately 30%. Through the spontaneous polarization effect of BTO, RP-based anode exhibits ultrafast discharging capability, showing the specific capability of 600 mAh g⁻¹ at 10 A g⁻¹. Such efficient strategy of utilizing the spontaneous polarization of piezoelectric materials to improve the bulk charge transport provides a forward-looking idea for the design of high-performance alloying anodes.

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The stress generated during the red phosphorus (RP) sodiumization process induces the spontaneous polarization of the piezoelectric material BaTiO₃ and effectively increases its dipole moment. Ultimately, the charge transfer behavior and rate performance of the RP anode are significantly improved.

Effective charge separation is crucial for efficient photocatalytic hydrogen production in metal–organic frameworks (MOFs). Herein, CdS-modified MOFs composites Y-TPTC/CdS and Y-TPTC-NH₂/CdS were synthesized with ordered porous structures and abundant active sites. Under visible light irradiation, Y-TPTC/CdS and Y-TPTC-NH₂/CdS exhibit optimal proportional hydrogen production rates of 1936 and 5650 µmol g⁻¹ h⁻¹, respectively, representing 9.4 and 27.1 times higher than that of pure CdS (205 µmol g⁻¹ h⁻¹). The introduction of amino groups effectively suppressed recombination of photogenerated charge carriers, facilitating more efficient charge transfer and significantly boosting photocatalytic hydrogen production activity. This work provides important insights for developing advanced composite photocatalysts with improved charge separation kinetics for enhanced solar-to-hydrogen conversion efficiency.

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