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Chinese yam (Dioscorea opposita), a traditional medicinal plant, has gained renewed interest in contemporary research due to its broad therapeutic potential. In this study, we developed an adhesive yam microgel through a series of peeling, grinding, sieving, and rehydration processes. Our in vitro experiments demonstrated that the yam microgel was noncytotoxic, effectively scavenged free radicals, and promoted cell migration. Additionally, the microgels exhibit good blood compatibility and biodegradability. In vivo, we first evaluated the hemostatic properties of the yam microgel in different hemorrhage models in rats. It demonstrated strong hemostatic capabilities because it could adsorb many blood cells and platelets, activate platelets, and facilitate coagulation. Furthermore, we observed that the yam microgel promotes the repair of acute skin tissue defects by enhancing cell proliferation and neovascularization as well as modulating the inflammatory response, thereby accelerating wound healing. Finally, we found that the yam microgel can serve as a biological adhesive, effectively promoting wound closure through a mechanism similar to its role in facilitating skin tissue repair. The design of a low-cost, safe, and effective yam microgel will provide a promising strategy for hemostasis and wound healing.

Safety hazards caused by flammable electrolytes have been major obstacles to the practical application of sodium-ion batteries (SIBs). The adoption of nonflammable all-phosphate electrolytes can effectively improve the safety of SIBs; however, traditional low-concentration phosphate electrolytes are not compatible with carbon-based anodes. Herein, we report an anion–cation interaction modulation strategy to design low-concentration phosphate electrolytes with superior physicochemical properties. Tris(2,2,2-trifluoroethyl) phosphate (TFEP) is introduced as a cosolvent to regulate the ion–solvent-coordinated (ISC) structure through enhancing the anion–cation interactions, forming the stable anion-induced ISC (AI-ISC) structure, even at a low salt concentration (1.22 M). Through spectroscopy analyses and theoretical calculations, we reveal the underlying mechanism responsible for the stabilization of these electrolytes. Impressively, both the hard carbon (HC) anode and Na4Fe2.91(PO4)2(P2O7) (NFPP) cathode work well with the developed electrolytes. The designed phosphate electrolyte enables Ah-level HC//NFPP pouch cells with an average Coulombic efficiency (CE) of over 99.9% and a capacity retention of 84.5% after 2000 cycles. In addition, the pouch cells can operate in a wide temperature range (−20 to 60 °C) and successfully pass rigorous safety testing. This work provides new insight into the design of the electrochemically compatibility electrolyte for high-safety and long-lifetime SIBs.

Feasible presodiation is indispensable in improving the energy density, lifespan and rate performance of sodium ion batteries. In this contribution, the fundamentals and advancements of presodiation methodology are comprehensively interpreted, encompassing the properties, underlying principles, associated approaches, and corresponding optimizations to present technological inferiorities.

Prussian blue analogues (PBAs) have gained significant popularity as cathode materials for sodium-ion batteries (SIBs) due to their remarkable features such as high capacity and convenient synthesis. However, PBAs usually suffer from kinetic problems during the electrochemical reactions due to sluggish Na+diffusion in the large crystals, resulting in low-capacity utilization and inferior rate capability. In this study, we present a facile etching method aiming at activating the sodium storage sites and accelerating the Na+transport of Na2NiFe(CN)6(denoted as NaNiHCF) by precisely controlling its morphologies. A progressive corner passivation phenomenon occurred in NaNiHCF during the etching process, which led to a substantial augmentation of the specific surface area as the morphology transitioned from a standard cube to a dice shape. Notably, by controlling the etching time, the obtained NaNiHCF-3 electrode exhibited boosted electrochemical performance with high reversible capacity of 83.5 mAh g−1(98.2% of its theoretical capacity), superior rate capability (71.2 mAh g−1at 10 C), and stable cycling life-span at different temperatures. Both experimental and computational methods reveal the remarkably reversible structural evolution process and improved Na+diffusion coefficient. We believe that this work can serve as an indispensable reference to tailor the structure of PBAs to obtain improved electrochemical performance.

The Li/CrOxbattery has gained attention in the construction of smart cities, aerospace, and national defense and military applications due to its high energy density and excellent rate performance. Developing a Li/CrOxbattery with high specific capacity, high energy density, excellent magnification performance, long storage life, and low cost is a primary goal. In this pursuit, the role of the electrolyte in battery performance for Li/CrOxprimary batteries cannot be underestimated. However, current research on Li/CrOxprimary batteries has primarily focused on electrode materials, with limited attention given to the electrolyte. Propylene carbonate (PC) solvent possesses a wide temperature range for melting and boiling points (−48.8 to 242 °C) and a high dielectric constant of 64.92. As a result, it is frequently used as a key component in electrolytes that operate under extreme temperatures and high rates. Nevertheless, its use in Li/CrOxbatteries remains limited. Developing electrolyte systems based on PC with a wide temperature range and high dielectric constant is crucial for the advancement of high-power and environmentally robust lithium primary batteries. In this study, we investigated the discharge behavior of CrOxin PC-based electrolytes and identified suitable electrolyte systems for high-current discharge, specifically a 1 mol∙L−1LiTFSI PC : DOL (1,3-dioxolane) = 1 : 2 ratio. We also demonstrated that the coordination number of solvent molecules in the solvation sheath layer around Li+ions and the solvated structure involved in coordination significantly influence the rate performance of Li/CrOxbattery systems in PC-based electrolytes. Reducing the coordination number of solvent molecules facilitates the desolvation behavior of solvated Li+, thereby enhancing the desolvation process on the material surface. Furthermore, lowering the coordination number of solvent molecules promotes the involvement of anions in the solvated sheath structure. When the coordination number of solvent molecules falls below 3, it tends to form a solvated coordination structure involving anions with a higher lowest unoccupied molecular orbital (LUMO) level. This enables anions to participate in forming a solid electrolyte interface (SEI), resulting in a thinner and denser SEI film that significantly improves battery performance. Ultimately, modifying the coordination number for PC-based electrolytes is a practical and effective approach to enhance the rate performance of solvated sheath structures. The coordination number and the solvated sheath structure of Li+in PC-based electrolytes have a profound impact on the high-current-discharge performance of the Li/CrOxbattery system. A lower coordination number and the participation of anions in the solvated sheath structure effectively accommodate the high-rate discharge characteristics of the Li/CrOxbattery. Among several selected electrolyte solvents, an electrolyte with DOL (a cyclic ether) and PC reduces the solvent's coordination number to less than four, thereby enabling high-rate discharge. Understanding these principles is crucial for advancing the application of PC-based electrolytes in high-rate Li/CrOxbattery systems.

This work reviewed the recent development in the exploration of different mixed polyanion cathode materials for sodium-ion batteries, and provided a comprehensive understanding of the structure-composition-performance relationship of mixed polyanion cathode materials, aiming to provide more inspiration for the design of advanced cathode materials for stable and high-energy batteries.

3D graphene-encapsulated Na2.4Fe1.8(SO4)3microspheres are synthesized by a facile spray-drying method. With the structural and compositional advantages, these cathodes exhibit enhanced sodium storage performance in terms of high specific capacity, excellent rate capability and superior cycling stability.

With many apparent advantages including high surface area, tunable pore sizes and topologies, and diverse periodic organic–inorganic ingredients, metal–organic frameworks (MOFs) have been identified as versatile precursors or sacrificial templates for preparing functional materials as advanced electrodes or high-efficiency catalysts for electrochemical energy storage and conversion (EESC). In this Mini Review, we first briefly summarize the material design strategies to show the rich possibilities of the chemical compositions and physical structures of MOFs derivatives. We next highlight the latest advances focusing on the composition/structure/performance relationship and discuss their practical applications in various EESC systems, such as supercapacitors, rechargeable batteries, fuel cells, water electrolyzers, and carbon dioxide/nitrogen reduction reactions. Finally, we provide some of our own insights into the major challenges and prospective solutions of MOF-derived functional materials for EESC, hoping to shed some light on the future development of this highly exciting field.

Polyanion-type Fe-based sulfates are one of the most promising cathode candidates for sodium-ion batteries (SIBs) due to the low cost and high voltage. However, their practical application is still hindered by the poor air stability. Herein, we report a novel anion-doped Na2.9Fe1.7(SO4)2.7(PO4)0.3cathode material with higher air stability and faster ion/electron transport kinetics compared to pristine Na2.6Fe1.7(SO4)3cathode as evidenced by first-principles calculations. The obtained Na2.9Fe1.7(SO4)2.7(PO4)0.3not only manifests a high discharge capacity of 100.4 mAh g-1with an operating voltage of ~3.57V (Na+/Na), but also exhibits excellent rate performance (~86.7 mAh g-1at 30C) and cycle stability over 6000 cycles (capacity retention of 76.3%). Particularly, Na2.9Fe1.7(SO4)2.7(PO4)0.3cathode still maintain its original crystal structural and sodium-storage property after exposure to air for one week. The high-voltage, long-life, and air-stable Na2.9Fe1.7(SO4)2.7(PO4)0.3could be a competitive cathode candidate for low-cost sodium-ion batteries.

Sodium-ion batteries (SIBs) are regarded as the most promising technology for large-scale energy storage systems. However, the practical application of SIBs is still hindered by the lack of applicable cathode materials. Herein, a novel phase-pure polyanionic Na8Fe5(SO4)9is designed and employed as a cathode material for SIBs for the first time. The Na8Fe5(SO4)9has an alluaudite-type sulfate framework and small Na+ion diffusion barriers. As expected, the as-synthesized Na8Fe5(SO4)9@rGO exhibits a high working potential of 3.8 ​V (versus Na/Na+), a superior reversible capacity of 100.2 mAh g−1at 0.2 ​C, excellent rate performance (∼80 mAh g−1at 10 ​C, ∼63 mAh g−1at 50 ​C), and an ultra-long cycling life (91.9% capacity retention after 10,000 cycles at 10 ​C, 81% capacity retention after 20,000 cycles at 50 ​C). We use various techniques and computational methods to comprehensively investigate the electrochemical reaction mechanisms of Na8Fe5(SO4)9@rGO.

Grid-scale energy storage systems with low-cost and high-performance electrodes are needed to meet the requirements of sustainable energy systems. Due to the wide abundance and low cost of sodium resources and their similar electrochemistry to the established lithium-ion batteries, sodium-ion batteries (SIBs) have attracted considerable interest as ideal candidates for grid-scale energy storage systems. In the past decade, though tremendous efforts have been made to promote the development of SIBs, and significant advances have been achieved, further improvements are still required in terms of energy/power density and long cyclic stability for commercialization. In this review, the latest progress in electrode materials for SIBs, including a variety of promising cathodes and anodes, is briefly summarized. Besides, the sodium storage mechanisms, endeavors on electrochemical property enhancements, structural and compositional optimizations, challenges and perspectives of the electrode materials for SIBs are discussed. Though enormous challenges may lie ahead, we believe that through intensive research efforts, sodium-ion batteries with low operation cost and longevity will be commercialized for large-scale energy storage application in the near future.

Tin disulfide (SnS2) is a promising anode material for sodium-ion batteries because of its high specific capacity. However, the low conductivity and large volume change during reaction with Na+ions greatly limit its practical application. Herein, a multistep templating method has been exploited for the rational design and synthesis of SnS2nanosheets confined in carbon nanotubes (SnS2@CNTs). To demonstrate the universality of this method, SnS2nanosheets confined in carbon nanoboxes (SnS2@CNBs) and hollow carbon nanospheres (SnS2@CNSs) have also been synthesized by simply changing the template in the reaction system. Due to their unique structural merits, the SnS2@CNTs, SnS2@CNBs, and SnS2@CNSs show improved sodium storage performance in terms of high specific capacity, good cycling stability, and superior rate capability.

High voltage, high rate, and cycling-stable cathodes are urgently needed for development of commercially viable sodium ion batteries (SIBs). Herein, we report a facile spray-drying method to synthesize graphene-scaffolded Na3V2(PO4)3microspheres (NVP@rGO), in which nanocrystalline Na3V2(PO4)3is embedded in graphene sheets to form porous microspheres. Benefiting from the highly conductive graphene framework and porous structure, the NVP@rGO material exhibits a high reversible capacity (115 mAh g–1at 0.2 C), long-term cycle life (81% of capacity retention up to 3000 cycles at 5 C), and excellent rate performance (44 mAh g–1at 50 C). The electrochemical properties of a full Na-ion cell with the NVP@rGO cathode and Sb/C anode are also investigated. The present results suggest promising applications of the NVP@rGO material as a high performance cathode for sodium ion batteries.

Olivine NaFePO4/C microsphere cathode is prepared by a facile aqueous electrochemical displacement method from LiFePO4/C precursor. The NaFePO4/C cathode shows a high discharge capacity of 111 mAh g–1, excellent cycling stability with 90% capacity retention over 240 cycles at 0.1 C, and high rate capacity (46 mAh g–1at 2 C). The excellent electrochemical performance demonstrates that the aqueous electrochemical displacement method is an effective and promising way to prepare NaFePO4/C material for Na-based energy storage applications. Moreover, the Na2/3FePO4intermediate is observed for the first time during the Na intercalation process through conventional electrochemical techniques, corroborating an identical two-step phase transition reaction both upon Na intercalation and deintercalation processes. The clarification of the electrochemical reaction mechanism of olivine NaFePO4could inspire more attention on the investigation of this material for Na ion batteries.

Mitigating high-voltage diffusion kinetic hindrance enables 4.6 V LiCoO2extreme fast charging capability, which is ascribed to more homogenous Li-ion de/intercalation at high voltage under high-rate current charge/discharge process.

Sodium metal is a promising anode for high-energy-density sodium rechargeable batteries (RSBs). However, the low Coulombic efficiency (CE) of the Na plating/stripping process and the problem of safety hinder their practical application. Herein, we report a facile strategy for employing the fluorinated phosphate solvents to realize highly reversible Na plating/stripping and improve the safety performance. The fluorinated phosphate molecules reduce the polarity of the solvent and lower the coordination number to Na+, which makes it possible to form the anion-induced ion–solvent-coordinated (AI-ISC) structures with high reduction tolerance. Moreover, the fluorination treatment enhances the oxidation resistance of the phosphate solvent, enabling compatibility with the high-voltage Na3V2(PO4)2F3(NVPF) cathode. As expected, the Na@Al//NVPF full cell with the as-prepared 0.9 M NaFSI/tris(2,2,2-trifluoroethyl) phosphate (TFEP) demonstrates a capacity retention of 83.4% after 200 cycles with an average CE of 99.6%. This work opens a new avenue for designing high-energy-density RSBs with improved safety performance.