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The practical applications of aqueous Zn/I2 batteries (AZIBs) operating within a wide temperature range are severely hindered by the uncontrolled shutting of polyiodide ions (I3−/ I5−) and rampant side reactions. In this study, a wide temperature tolerant polyanionic hydrogel (borax‐bacteria cellulose / p(AMPS‐AM)) with ion selective permeability is designed for inhibiting shutting effect and side reactions under extreme temperatures range from −50 to 50 °C. The zincophilic R−SO3− significantly enhances the transport of Zn2+ cations and promotes uniform growth of Zn metal along the (002) plane. Moreover, the abundant hydrophilic groups in hydrogels effectively suppress both the hydrogen evolution reaction and the formation of by‐products by reducing the water reactivity. Furthermore, theoretical calculations, visualization experiment and in situ Raman spectroscopy confirm that R−SO3− group effectively hinders the shuttle process of I3−/I5− anions through electrostatic repulsion. Consequently, this gel electrolyte facilitates the ultra‐stable Zn/I2 full cell at a low current density of 2 C over a wide temperature range of 100 °C. A Zn/I2 pouch cell with a low negative/positive capacity ratio of 3.3 exhibits a stable performance over 350 cycles with an impressive high‐areal capacity of 2.03 mA h cm−2, thereby establishing a solid foundation for its practical applications. [ABSTRACT FROM AUTHOR]

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]

In the work, a facile yet efficient self-sacrifice strategy is smartly developed to scalably fabricate hierarchical mesoporous bi-component-active ZnO/ZnFe2O4 (ZZFO) sub-microcubes (SMCs) by calcination of single-resource Prussian blue analogue of Zn3[Fe(CN)6]2 cubes. The hybrid ZZFO SCMs are homogeneously constructed from well-dispersed nanocrstalline ZnO and ZnFe2O4 (ZFO) subunites at the nanoscale. After selectively etching of ZnO nanodomains from the hybrid, porously assembled ZFO SMCs with integrate architecture are obtained accordingly. When evaluated as anodes for LIBs, both hybrid ZZFO and ZFO samples exhibit appealing electrochemical performance. However, the as-synthesized ZZFO SMCs demonstrate even better electrochemical Li-storage performance, including even larger initial discharge capacity and reversible capacity, higher rate behavior and better cycling performance, particularly at high rates, compared with the single ZFO, which should be attributed to its unique microstructure characteristics and striking synergistic effect between the bi-component-active, well-dispersed ZnO and ZFO nanophases. Of great significance, light is shed upon the insights into the correlation between the electrochemical Li-storage property and the structure/component of the hybrid ZZFO SMCs, thus, it is strongly envisioned that the elegant design concept of the hybrid holds great promise for the efficient synthesis of advanced yet low-cost anodes for next-generation rechargeable Li-ion batteries. [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]