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Although hard carbon (HC) demonstrates superior initial Coulombic efficiency, cycling durability, and rate capability in ether‐based electrolytes compared to ester‐based electrolytes for sodium‐ion batteries (SIBs), the underlying mechanisms responsible for these disparities remain largely unexplored. Herein, ex situ electron paramagnetic resonance (EPR) spectra and in situ Raman spectroscopy are combined to investigate the Na storage mechanism of HC under different electrolytes. Through deconvolving the EPR signals of Na in HC, quasi‐metallic‐Na is successfully differentiated from adsorbed‐Na. By monitoring the evolution of different Na species during the charging/discharging process, it is found that the initial adsorbed‐Na in HC with ether‐based electrolytes can be effectively transformed into intercalated‐Na in the plateau region. However, this transformation is obstructed in ester‐based electrolytes, leading to the predominant storage of Na in HC as adsorbed‐Na and pore‐filled‐Na. Furthermore, the intercalated‐Na in HC within the ether‐based electrolytes contributes to the formation of a uniform, dense, and stable solid–electrolyte interphase (SEI) film and eventually enhances the electrochemical performance of HC. This work successfully deciphers the electrolyte‐dominated Na+ storage mechanisms in HC and provides fundamental insights into the industrialization of HC in SIBs. [ABSTRACT FROM AUTHOR]

Transition metal sulphides based on conversion reaction mechanism have attracted much attention as anode materials for sodium‐ion batteries owing to their theoretical specific capacity and potential long lifespan. The unsatisfactory Coulombic efficiency, however, inhabits the cycling lifespan due to the intermediate polysulfide formation (Na2Sx; 4≤x≤6) and chain reactions. To enhance the polysulfide polysulfide adsorption capability and capacity, a hybrid with synergistic sodium storage and polysulfide adsorption capability was designed, in which massive CoS2 nanoparticles (CoS2 NP) were utilized as electrons supplier to enhance the adsorption energy of three‐dimensional nitrogen‐doped carbon (3D‐NC) framework towards sodium polysulfide. Combining the experimental and computational results, the encapsulated CoS2 can dramatically optimize the local electronic structure and function as a powerful electron reservoir to increase the effective adsorption to Na2Sx (4≤x≤6). Meanwhile, the electron transferring between CoS2 NP and 3D‐NC can facilitate the conversion of Na2S to Na2Sx. An ultra‐high initial Coulombic efficiency of 98.05 % and 98.38 % can be achieved at current densities of 0.06 A g−1 and 0.4 A g−1, respectively. Beneficial from the high reversible capability, a superior cycling lifespan is obtained up to 800 long cycles at current densities of 0.6 A g−1. [ABSTRACT FROM AUTHOR]

Economical efficient anode materials play an important role in low‐temperature sodium‐ion batteries (SIBs). Tunnel‐type structured Na2Ti6O13@C nanowires were synthesized and utilized as anode material for low‐temperature SIBs. The appropriate interlayer spacing for sodium ion insertion and short diffusion pathway can accelerate the sodium ion kinetics and decrease the apparent activation energy at low temperature. The diffusion apparent activation energy and activation energy for Na2Ti6O13@C were calculated to be 42.0 kJ mol−1 and 15.3 kJ mol−1 with the sodium ion diffusion coefficients about 10−12 cm2 s−1. The Na2Ti6O13@C nanowires exhibit a high reversible capacity of 100 mAh g−1 at 0 °C with 99.6 % retention after 200 cycles at 0.5 C. Coupling with the sodium vanadium phosphate as cathode, the assembled Na2Ti6O13@C||NVP full‐cell can keep a 65 % capacity retention after 175 cycles at 0 °C. This work presents that Na2Ti6O13@C nanowires can be an ideal type of anode active materials for low‐temperature SIBs. [ABSTRACT FROM AUTHOR]

Double carbon-embedded Na3V2(PO4)3 (DC-NVP) nanocomposites were prepared via in situ growth of NVP@C nanoparticles on carbon nanotubes (CNTs). Beneficial of a high electronic conductivity network and structure stability, the DC-NVP nanocomposite as an anode of sodium ion batteries (SIBs) reveals outstanding electrochemical properties, delivering ultra-long cycle life with a first charge capacity of 78 mA h g−1 at 50 C and a capacity loss of 0.006%/cycle over 8000 cycles. The NVP//NVP full cells, fabricated by the DC-NVP nanocomposites as bipolar electrode, exhibit a discharge capacity of 72.1 mA h g−1 at 20 C after 5000 cycles and a corresponding capacity retention of 81%. The remarkable performance of DC-NVP nanocomposites is ascribed to that of the unique double carbon-embedded nanostructure, which possesses good electronic conductivity, larger electrode-electrolyte contact area, fast electron and ion transportation, and structural stability. [ABSTRACT FROM AUTHOR]

Metabolites in atrial fibrillation (AF) were characterized to further explore the molecular mechanisms of AF by integrating metabolic, phenomic and genomic data. Gene expression data on AF (E-GEOD-79768) were downloaded from the EMBL-EBI database, followed by identification of differentially expressed genes (DEGs) which were used to construct gene-gene network. Then, multi-omics composite networks were constructed. Subsequently, random walk with restart was expanded to a multi-omics composite network to identify and prioritize the metabolites according to the AF-related seed genes deposited in the OMIM database, the whole metabolome as candidates and the phenotype of AF. Using the interaction score among metabolites, we extracted the top 50 metabolites, and identified the top 100 co-expressed genes interacted with the top 50 metabolites. Based on the FDR <0.05, 622 DEGs were extracted. In order to demonstrate the intrinsic mode of this method, we sorted the metabolites of the composite network in descending order based on the interaction scores. The top 5 metabolites were respectively weighed potassium, sodium ion, chitin, benzo[a]pyrene-7,8-dihydrodiol-9,10-oxide, and celebrex (TN). Potassium and sodium ion possessed higher degrees in the subnetwork of the entire composite network and the co-expressed network. Metabolites such as potassium and sodium ion may provide valuable clues for early diagnostic and therapeutic targets for AF. [ABSTRACT FROM AUTHOR]

Abstract: An integrated, free‐standing, and binder‐free type of flexible anode electrode is fabricated from numerous holey‐structured, 2D nickel‐based phosphide nanosheets connected with carbon nanotubes. This electrode architecture can not only uniformly disperse the nanosheets throughout the whole electrode to avoid aggregation or detachment, but also provide an ideal sodium ion and electrolyte diffusion and penetration network with high electronic conductivity. Meanwhile, bimetallic phosphide formation by introducing secondary metal species will lead to a synergistic effect to modify the electrochemical properties. Due to the excellent compositional and structural characteristics of this electrode, it delivers superior performance. This designed flexible anode with Ni1.5Co0.5Px nanosheets demonstrates a reversible capacity of 496.4 mAh g−1 at 0.5 C and a good rate capacity of 276.1 mAh g−1 at 8 C. Meanwhile, this connected integrated network woven from carbon nanotubes can effectively restrain volumetric expansion and shrinkage, and affect the conversion reaction products formation as well, from large‐sized microspheres to film structure, which is primarily credited with the improvement in electrochemical performance. This work may open up a new path for the synthesis of morphology‐controlled phosphides and promote the further development of flexible devices. [ABSTRACT FROM AUTHOR]

Abstract: Extensive effort is being made into cathode materials for sodium‐ion battery to address several fatal issues, which restrict their future application in practical sodium‐ion full cell system, such as their unsatisfactory initial Coulombic efficiency, inherent deficiency of cyclable sodium content, and poor industrial feasibility. A novel air‐stable O3‐type Na[Li0.05Mn0.50Ni0.30Cu0.10Mg0.05]O2 is synthesized by a coprecipitation method suitable for mass production followed by high‐temperature annealing. The microscale secondary particle, consisting of numerous primary nanocrystals, can efficiently facilitate sodium‐ion transport due to the short diffusion distance, and this cathode material also has inherent advantages for practical application because of its superior physical properties. It exhibits a reversible capacity of 172 mA h g−1 at 0.1 C and remarkable capacity retention of 70.4% after 1000 cycles at 20 C. More importantly, it offers good compatibility with pristine hard carbon as anode in the sodium‐ion full cell system, delivering a high energy density of up to 215 W h kg−1 at 0.1 C and good rate performance. Owing to the high industrial feasibility of the synthesis process, good compatibility with pristine hard carbon anode, and excellent electrochemical performance, it can be considered as a promising active material to promote progress toward sodium‐ion battery commercialization. [ABSTRACT FROM AUTHOR]

Abstract: Sodium‐ion batteries (SIBs) have been considered as the most promising candidate for large‐scale energy storage system owing to the economic efficiency resulting from abundant sodium resources, superior safety, and similar chemical properties to the commercial lithium‐ion battery. Despite the long period of academic research, how to realize sodium‐ion battery commercialization for market applications is still a great challenge. Thus, from the perspective of future practical application, this review will identify the factors that are restricting commercialization, and evaluate the existing active materials and sodium‐ion‐based full‐cell system. The design and development trends that are needed for SIBs to meet the requirements of practical applications in large‐scale energy storage will also be discussed in detail. [ABSTRACT FROM AUTHOR]

Sodium-ion battery has captured much attention due to the abundant sodium resources and potentially low cost. However, it suffers from poor cycling stability and low diffusion coefficient, which seriously limit its widespread application. Here, K3V2(PO4)3/C bundled nanowires are fabricated usinga facile organic acid-assisted method. With a highly stable framework, nanoporous structure, and conductive carbon coating, the K3V2(PO4)3/C bundled nanowires manifest excellent electrochemical performances in sodium-ion battery. A stable capacity of 119 mAh g−1 can be achieved at 100 mA g−1. Even at a high current density of 2000 mA g−1, 96.0% of the capacity can be retained after 2000 charge-discharge cycles. Comparing with K3V2(PO4)3/C blocks, the K3V2(PO4)3/C bundled nanowires show significantly improved cycling stability. This work provides a facile and effective approach to enhance the electrochemical performance of sodium-ion batteries. [ABSTRACT FROM AUTHOR]

Sodium-ion batteries (SIBs) are considered a potential alternative to lithium-ion batteries (LIBs) for energy storage due to their low cost and the large abundance of sodium resources. The search for new anode materials for SIBs has become a vital approach to satisfying the ever-growing demands for better performance with higher energy/power densities, improved safety and a longer cycle life. Recently, antimony (Sb) has been extensively researched as a promising candidate due to its high specific capacity through an alloying/dealloying process. In this review article, we will focus on different categories of the emerging Sb based anode materials with distinct sodium storage mechanisms including Sb, two-dimensional antimonene and antimony chalcogenide (Sb2S3 and Sb2Se3). For each part, we emphasize that the novel construction of an advanced nanostructured anode with unique structures could effectively improve sodium storage properties. We also highlight that sodium storage capability can be enhanced through designing advanced nanocomposite materials containing Sb based materials and other carbonaceous modification or metal supports. Moreover, the recent advances in operando/in-situ investigation of its sodium storage mechanism are also summarized. By providing such a systematic probe, we aim to stress the significance of novel nanostructures and advanced compositing that would contribute to enhanced sodium storage performance, thus making Sb based materials as promising anodes for next-generation high-performance SIBs. [ABSTRACT FROM AUTHOR]

With the increasing energy crisis and environmental pollution, rechargeable aqueous Zn‐based batteries (AZBs) are receiving unprecedented attention due to their list of merits, such as low cost, high safety, and nontoxicity. However, the limited voltage window, Zn dendrites, and relatively low specific capacity are still great challenges. In this work, a new reaction mechanism of reversible Mn2+ ion oxidation deposition is introduced to AZBs. The assembled Mn2+/Zn2+ hybrid battery (Mn2+/Zn2+ HB) based on a hybrid storage mechanism including Mn2+ ion deposition, Zn2+ ion insertion, and conversion reaction of MnO2 can achieve an ultrawide voltage window (0–2.3 V) and high capacity (0.96 mAh cm−2). Furthermore, the carbon nanotubes coated Zn anode is proved to effectively inhibit Zn dendrites and control side reaction, hence exhibiting an ultrastable cycling (33 times longer than bare Zn foil) without obvious polarization. Benefiting from the optimal Zn anode and highly reversible Mn2+/Zn2+ hybrid storage mechanism, the Mn2+/Zn2+ HB shows an excellent cycling performance over 11 000 cycles with a 100% capacity retention. To the best of the authors' knowledge, it is the highest reported cycling performance and wide voltage window for AZBs with mild electrolyte, which may inspire a great insight into designing high‐performance aqueous batteries. [ABSTRACT FROM AUTHOR]

Chalcogenides have attracted great attention as functional materials in optics, electronics, and energy-related applications due to their typical semiconductor properties. Among those chalcogenides, Sb2S3 holds great promise in energy storage field, especially as an anode material for alkali metal (Li, Na, and K) batteries. In this work, a one-dimensional coaxial Sb2S3@PPy is investigated as a versatile and robust anode in three kinds of alkali metal batteries for the first time, and the energy storage mechanism of these batteries is systematically discussed. As an anode material for sodium ion batteries (SIBs) and potassium ion batteries (KIBs), Sb2S3@PPy exhibits high reversible capacity and impressive cycle lifespan. Sb2S3@PPy anode demonstrates an adsorption behavior that has a significant influence on its sodium storage behavior, providing a universal model for studying the application of chalcogenide compounds. [ABSTRACT FROM AUTHOR]

Developing multielectron reaction electrode materials is essential for achieving high specific capacity and high energy density in secondary batteries; however, it remains a great challenge. Herein, Na3MnTi(PO4)3/C hollow microspheres with an open and stable NASICON framework are synthesized by a spray‐drying‐assisted process. When applied as a cathode material for sodium‐ion batteries, the resultant Na3MnTi(PO4)3/C microspheres demonstrate fully reversible three‐electron redox reactions, corresponding to the Ti3+/4+ (≈2.1 V), Mn2+/3+ (≈3.5 V), and Mn3+/4+ (≈4.0 V vs Na+/Na) redox couples. In situ X‐ray diffraction results reveals that both solid‐solution and two‐phase electrochemical reactions are involved in the sodiation/desodiation processes. The high specific capacity (160 mAh g−1 at 0.2 C), outstanding cyclability (≈92% capacity retention after 500 cycles at 2 C), and the facile synthesis make the Na3MnTi(PO4)3/C a prospective cathode material for sodium‐ion batteries. NASICON‐structured Na3MnTi(PO4)3/C demonstrates fully reversible three‐electron redox reactions, corresponding to the Ti3+/4+ (2.1 V), Mn2+/3+ (3.5 V), and Mn3+/4+ (4.0 V vs Na+/Na) redox couples. The Na3MnTi(PO4)3/C delivers a high reversible sodium storage capacity and a durable cycling performance, which make the Na3MnTi(PO4)3/C a highly promising cathode material for sodium storage. [ABSTRACT FROM AUTHOR]

• New explored two-dimensional NbSSe material for low temperature SIBs. • Inducing interlayer anionic ligands strategy. • Consolidate the interlayer band gap and optimize the electronic structure. • Excellent rate capability and lifespan can be exhibited at 0 °C. Sodium ion batteries performance at low temperature is extremely restricted by the sluggish kinetics of sodium ions diffusion within active materials and interface. The strategy of inducing interlayer anionic ligands in two-dimensional NbSSe nanoplates is employed to consolidate the interlayer band gap and optimize the electronic structure. It combines complementary benefits from two kinds of anionic ligands with high conductivity and good affinity with sodium ions at low temperature. The explored two-dimensional NbSSe nanoplates can provide an acceptable rate and lifespan electrochemical performance, delivering a high reversible capacity of 136 mAh g−1 at 0 °C with the 92.67% retention after 500 cycles at 0.2 C. The totally sodium storage capacity are contributed from the combination of capacitive and diffusion behaviours. The sodium ion diffusion coefficients are in the range of 3.23 × 10-13 to 4.47 × 10-12 at 0 °C. The diffusion apparent activation energy is 54.92 kJ mol−1 and the activation energy is 65.97 kJ mol−1. The explored two-dimensional NbSSe nanoplates can extend the sodium ion battery application field, particularly at low temperatures. [ABSTRACT FROM AUTHOR]