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As one of the most promising cathode materials for sodium-ion batteries, Prussian blue analogs (PBAs) cathodes face challenges in terms of poor cycling stability owing to their poor interfacial stability. Poor interfacial stability often leads to irreversible behaviors such as dissolution of cathode transition metals and catalytic decomposition of solvents. Herein, a novel metal ion-coordinated cross-linked quasi-solid-state polymer electrolyte was prepared via an in situ method using a four-armed cross-linker, where the denser and more efficient three-dimensional network renders the electrolyte with excellent chemical and electrochemical stabilities, minimizes catalytic decomposition side reactions and improves the interfacial stability of high-voltage PBAs cathodes. Moreover, the combination of in situ technology with Ti-MOFs fillers affords a highly compatible electrode/electrolyte interphase and an organic/inorganic composite Na+ conduction pathway, which accelerates Na+ transport and enhances interfacial stability. Thus, the as-designed polymer electrolyte exhibits an ionic conductivity of 3.85 mS cm−1 and extended oxidation stability of 5.1 V, coupled with improved mechanical strength and safety. The CFM-PBAs‖Na battery demonstrates excellent rate performance and cycling stability (with an average coulombic efficiency of nearly 100% over 2000 cycles). Furthermore, the high-capacity FM-PBAs‖Na battery achieves an ultra-high energy density of 445 Wh kg−1, showcasing significant potential for high energy-density and long-life PBAs cathodes. [ABSTRACT FROM AUTHOR]

Despite their low cost and high specific capacity, the practical use of monoclinic Mn‐based Prussian blue analogs (Mn‐PBAs) is limited by poor cycling stability, primarily due to the structural degradation caused by the multiple phase transitions and Jahn–Teller effect associated with Mn3+ ions throughout the entire cycle. Herein, by synergistic incorporation of low‐cost Cu and Fe into the manganese sites of Mn‐PBAs, the ternary PBAs (T‐PBAs) achieve solid solution reaction of Na+ extraction and insertion, successfully eliminating the inherent multi‐phase transition from the sodium storage mechanism of T‐PBAs. Ex situ analysis and density functional theory calculations are employed to confirm that T‐PBAs consistently maintain a cubic phase with smaller lattice distortion rather than occur in conventional three‐phase transition during the charging and discharging processes, forcefully inhibiting the structural degradation of T‐PBAs. Therefore, the T‐PBAs showcase unprecedented cycling stability at both room temperature (10 000 cycles at 1 A g−1) and −20 °C (over 3000 h, 4200 cycles at 0.2 A g−1 without distinct capacity degradation), More importantly, when paired with commercial hard carbon, the T‐PBAs based sodium‐ion batteries exhibit excellent capacity retention (2000 cycles 76.8%), showcasing their immense potential in practical applications. [ABSTRACT FROM AUTHOR]

Microcatheters capable of active guidance have been proven to be effective and efficient solutions to interventional surgeries for cardiovascular and cerebrovascular diseases. Herein, a novel microcatheter made of two biocompatible materials, shape memory alloy (SMA) and polyethylene (PE), is proposed. It consists of a reconfigurable distal actuator and a separate polyethylene catheter. The distal actuator is created via embedding U-shape SMA wires into the PE base, and its reconfigurability is mainly dominated by the shape memory effect (SME) of SMA wires, as well as the effect of thermal mismatch between the SMA and PE base. A mathematical model was established to predict the distal actuator's deformation, and the analytical solutions show great agreement with the finite element results. Structural optimization of such microcatheters was carried out using the verified analytical model, followed by fabrication of some typical prototypes. Experimental testing of their mechanical behaviors demonstrates the feasibility of the structural designs, and the reliability and accuracy of the mathematical model. The active microcatheter, together with the prediction model, will lay a solid foundation for rapid development and optimization of active navigation strategies for vascular interventions. [ABSTRACT FROM AUTHOR]

Prussian blue analogs (PBAs) have been regarded as competitive cathode materials for sodium-ion batteries due to their low-cost and easy synthesis. Nevertheless, the practical application of PBAs is limited by their intrinsic poor electronic conductivity and structural degradation. Herein, a unique high entropy (HE) Prussian blue Analogs encapsulated by three-dimensional carbon (HE-PBAs@C) was for the first time designed and synthesized by combining the merits of HE and 3D confinement effect originating from carbon wrapping (CW). The HE strategy guarantees the inherent stability of PBAs and promotes accelerated Na+ diffusion, while the CW technique serves a dual purpose by enhancing electronic conductivity and mitigating lattice distortion through the 3D confinement effect. As a result, the HE-PBAs@C cathode exhibits impressive electrochemical performance, including high specific capacity (120.2 mA h g−1 at 10 mA g−1), outstanding rate performance (73.0 mA h g−1 at 4 A g−1), excellent capacity retention (80.1% after 4000 cycles at 2 A g−1) and unprecedented stability in the ambient environment. Furthermore, the HE-PBAs@C cathode demonstrates excellent compatibility with both hard carbon (700 cycles 95.4%) and NaTi2(PO4)3 (1000 cycles 98.1%) anodes in full cells, highlighting its promising potential for large-scale energy storage applications. [ABSTRACT FROM AUTHOR]

Soft crawling robots have attracted considerable attentions due to their merits of flexibility, safety, cost, and their unique applications that are not available for the rigid robots. However, poor precision resulting from the strongly nonlinear reconfiguration prevents such soft robots from wider applications. This paper reported a novel SMA spring driven soft crawling robot with feet of constant curvature, and the constant height of the feet during crawling enabled effective alleviation of the nonlinearity of the robotic reconstruction. An analytical static model for the step length of the robot's crawling gait was built based on 11 independent design parameters, and the influential significance of each parameter was parametrically studied based on the static model. These parameters were then qualitatively classified as strong, medium, and weak factors based on their influences on the theoretical step length of the crawling robot, among which the minimum and the maximum bending angles and the length of the silicone body functioned as the dominant factors. This work provides an efficient approach to the design, prediction, evaluation, and optimization of such soft crawling robots for diverse application surroundings. [ABSTRACT FROM AUTHOR]

Iron-based phosphate Na 4 Fe 3 (PO 4 ) 2 (P 2 O 7 ) (NFPP) has been regarded as the most promising cathode for sodium-ion batteries (SIBs) thanks to its cost-effectiveness and eco-friendliness. However, it is in a predicament from the intrinsic low ionic/electronic conductivity, becoming a great challenge for its practical application. Herein, the significant roles of the low-energy 3p-orbital and transition metal vacancies are emphasized in facilitating charge rearrangement and reconstructing ion-diffusion channels, from the perspectives of crystallography and electron interaction for the first time, and the modification mechanism is fully explored by various characterizations and theoretical calculations. As proof of this concept, the designed Na 4 Fe 2.85 Al 0.1 (PO 4 ) 2 (P 2 O 7 ) (NF 2.85 A 0.1 PP) delivers prominent electrochemical performance, achieving high energy density (≈350 Wh kg⁻¹), superior kinetics (62 mAh g⁻¹ at 10 A g⁻¹), excellent power density (23 kW kg⁻¹, 143 Wh kg⁻¹), and extraordinary cycling stability (with negligible attenuation after 10 000 cycles). This work provides a brand-new perspective for designing ultra-endurable high-rate polyanion cathodes., (© 2025 Wiley‐VCH GmbH.)

Na 4 Fe 3 (PO 4 ) 2 (P 2 O 7 ) (NFPP) has been considered a promising cathode material for sodium-ion batteries (SIBs) owing to its environmental friendliness and economic viability. However, its electrochemical performance is constrained by connatural low electronic conductivity and inadequate sodium ion diffusion. Herein, a high-entropy substitution strategy is employed in NFPP to address these limitations. Ex situ X-ray diffraction analysis reveals a single-phase electrochemical reaction during the sodiation/desodiation processes and the increased configurational entropy in HE-NFPP endows an enhanced structure, which results in a minimal volume variation of only 1.83%. Kinetic analysis and density functional theory calculation further confirm that the orbital hybrid synergy of high-entropy transition metals offers a favorable electronic structure, which efficaciously boosts the charge transfer kinetics and optimizes the sodium ion diffusion channel. Based on this versatile strategy, the as-prepared high-entropy Na 4 Fe 2.5 Mn 0.1 Mg 0.1 Co 0.1 Ni 0.1 Cu 0.1 (PO 4 ) 2 (P 2 O 7 ) (HE-NFPP) cathode can deliver a prominent rate performance of 55 mAh g -1 at 10 A g -1 and an ultra-long cycling lifespan of over 18 000 cycles at 5 A g -1 . When paired with a hard carbon (HC) anode, HE-NFPP//HC full cell exhibits a favorable cycling durability of 1000 cycles. This high-entropy engineering offers a feasible route to improve the electrochemical performance of NFPP and provides a blueprint for exploring high-performance SIBs., (© 2024 Wiley‐VCH GmbH.)