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Sodium‐ion batteries (SIBs) with wide operating temperature are regarded as promising candidates for large‐scale energy storage systems. However, SIBs operating under elevated temperature aggravate the electrolyte decomposition with unstable cathode‐electrolyte interphase (CEI), causing a rapid capacity degradation. Herein, anion receptor tris(pentafluorophenyl)borane (TPFPB) is selected as electrolyte additive to construct robust NaF‐rich CEI. The strong interactions between anion and TPFPB via the electron‐deficient boron atoms weaken ClO4− solvation and promote the coordination capability between solvents and Na+ cations, demonstrating greatly improved oxidative stability. Na3V2(PO4)3 cathode in TPFPB‐containing electrolyte delivers long‐term stability with a capacity retention of 86.9% after 100 cycles at a high cut‐off voltage of 4.2 V (vs. Na+/Na) and a high temperature of 60 °C. Besides, TPFPB also works well with enhanced performance over a temperature range from −30 to 60 °C. This study proposes a prospective method by manipulating the solvation chemistry for constructing high‐temperature rechargeable SIBs. [ABSTRACT FROM AUTHOR]

Organic compounds have become a potentially important choice for a new generation of energy-storage electrode materials due to their designability, flexibility, green sustainability, and abundance. However, the applications of organic electrode materials are still limited because of their dissolution in electrolytes and low electrical conductivity, which in turn cause poor cycling stability. Here, for the first time, we report 2-amino-4-thiazole-acetic acid (ATA) and its sodium salt, sodium 2-amino-4-thiazol-derived polymer (PATANa), as an anode. The PATANa showed a two-dimensional (2D) nanosheet structure, offering a larger contact area with the electrolyte and a shorter ion-migration path, which improved the ion-diffusion kinetics. The polymer showed excellent cycling stability and outstanding rate capability when tested as an anode for sodium-ion batteries (SIBs). It could deliver a high reversible specific capacity of 303 mA h g−1 at 100 mA g−1 for 100 cycles and maintain a high discharge capacity of 190 mA h g−1 after 1000 long cycle numbers even at a high current density of 1000 mA g−1. This approach of salinizing the polymer opens a new way to develop anode materials for sodium-ion batteries. [ABSTRACT FROM AUTHOR]

Among the various semiconductor materials, zinc telluride possesses the lowest electron affinity and ultrafast charge separation capability, facilitating improved charge transfer kinetics. In addition, ZnTe has a relatively high density, contributing to high volumetric capacity. Here, 1D N‐doped carbon‐coated ZnTe core‐shell nanowires (ZnTe@C) are designed and prepared via a facile ion‐exchange and carbonization technique. When evaluated as anode for metal ion batteries, it demonstrates superior electrochemical performance in both Li and Na ion storage, including high gravimetric and volumetric capacities (1119 mA h g−1 and 906 mA h cm−3, respectively, at 100 mA g−1 for Li ion storage), excellent high‐rate capability, and long‐term cycling stability. This remarkable electrochemical performance is attributed to the low electron affinity and high density of ZnTe, and the amorphous nature of the N‐doped carbon layer in the heterostructured ZnTe@C nanowires, which not only provide fast charge transfer paths, but also effectively maintain the structural and electrical integrity of the ZnTe. The strategy of embedding high density and high‐performance active materials in highly conductive nanostructures represents an effective way of achieving electrode materials with excellent gravimetric and volumetric capacities towards superior energy storage systems. [ABSTRACT FROM AUTHOR]

The development of stable electrode materials for sodium‐ion batteries (NIBs) with excellent rate capacity, high volumetric/gravimetric capacity, and ultralong‐term cycling stability still remains a challenge. Herein, a novel strategy for the synthesis of edge‐nitrogen‐rich carbon dots pillared graphene blocks (N‐CDGB) through self‐polymerization of aniline into graphene oxide blocks, and subsequent carbonization is developed. Due to high bulk density (1.5 g cm−3) and integrated lamellar structure with large edge‐interlayer spacing (4.2 Å) pillared by nitrogen‐doped carbon dots (95% edge‐nitrogen content), the dense N‐CDGB shows robust structural stability, fast ion/electron transfer pathways, and more active sites for sodium storage. As a result, the N‐CDGB electrode exhibits ultrahigh reversible volumetric and gravimetric capacities (780 mAh cm−3/520 mAh g−1 at 0.02 A g−1) far exceeding those of graphene (108 mAh cm−3/290 mAh g−1) and hard carbon (297 mAh cm−3/311 mAh g−1), excellent rate capability (118 mAh g−1/177 mAh cm−3 at 10 A g−1), and superior cycling stability up to 10 000 cycles with almost no capacity loss at 10 A g−1. This work signifies the superiority of densely pillared structure in the future development of NIBs with high volumetric/gravimetric capacity and ultralong‐term cycling stability. Edge‐nitrogen‐rich carbon dots pillared graphene blocks synthesized from natural graphite exhibit ultrahigh volumetric/gravimetric capacities (780 mAh cm−3/520 mAh g−1 at 0.02 A g−1), excellent rate performance, and ultralong cycle life. [ABSTRACT FROM AUTHOR]

Sodium ion batteries (SIBs) have been considered as a promising candidate to supersede lithium ion batteries, however, the lack of suitable electrode materials for efficient Na-storage still hinders its practical use. Hence, this work reports a general and effective way to in-situ construction of heterostructured SnSe/SnTe nanodots encapsulated in nitrogen-doped mesoporous carbon matrix (SnSe/SnTe@N-CNFs). In such unique architecture, the porous N-CNFs matrix cannot only provide high electronic/ion conductivity but also alleviate the volume change of SnSe and SnTe, leading to rapid kinetics and robust structure, whereas the ultrasmall SnSe/SnTe heterostructure with built-in interfacial driving force can promote charge transfer kinetics. Meanwhile, the abundant defective sites induced from high-level N-doping is beneficial to Na+ storage. Besides, the formed Sn–C, Se–C, and Te–C bonds can improve the interfacial interaction between SnSe/SnTe and N-CNFs, thus enhancing electronic conductivity, suppressing the aggregation and detachment of active components, and ensuring rapid kinetics and structural integrity. When evaluated as an anode for SIBs, the as-prepared SnSe/SnTe@N-CNFs exhibits high reversible capacity, remarkable cycling stability, and superior rate capability. This work can offer an efficient and universal strategy for designing advanced anode materials with exceptional performance. [Display omitted] • Highly conductive and porous N-CNFs matrix alleviates the volume change of SnSe/SnTe. • Strong chemical bonds between SnSe/SnTe and N-CNFs improve interfacial interaction. • High-level N-doping affords abundant defective sites for Na+ storage. • Storage mechanism and kinetics of Na+ in SnSe/SnTe@N-CNFs anode is revealed. • SnSe/SnTe@N-CNFs heterostructure exhibits superior electrochemical performance. [ABSTRACT FROM AUTHOR]