Avoiding severe structural distortion, irreversible phase transition, and realizing the stabilized multielectron redox are vital for promoting the development of high-performance NASICON-type cathode materials for sodium-ion batteries (SIBs). Herein, a high-entropy Na3.45V0.4Fe0.4Ti0.4Mn0.45Cr0.35(PO4)3 (HE-Na3.45TMP) cathode material is prepared by ultrafast high-temperature shock, which inhibits the possibility of phase separation and achieves reversible and stable multielectron transfer of 2.4/2.8 e- at voltage range of 2.0-4.45/1.5-4.45 V versus Na+/Na (the capacity of 137.2/162.0 mAh g-1). The galvanostatic charge/discharge and in-situ X-ray diffraction tests indicate the sequential redox reactions and approximate solid solution phase transition behavior of HE-Na3.45TMP. Density functional theory calculations analyze the migration pathways and energy barriers, further confirming the superior reaction kinetics of HE-Na3.45TMP. Accordingly, the HE-Na3.45TMP exhibits outstanding wide temperature applicability and can operate stably in the temperature range of -50-60 °C, accompanied by a capacity retention of 92.8% after 400 cycles at -40 °C and a capacity of 73.7 mAh g-1 even at -50 °C. The assembled hard carbon//HE-Na3.45TMP full-cell offers an energy density of ≈301 Wh kg-1 based on total cathode and anode active mass, verifying the application feasibility of HE-Na3.45TMP. This work provides an innovative and ultrafast pathway to rationally fabricate high-performance cathodes for SIBs.

With the continuous advancement of industrialization, sodium-ion batteries (SIBs) need to operate in various challenging circumstances, particularly in extremely cold conditions. However, at ultra-low temperatures, the reduced ionic conductivity and sluggish Na + migration of commonly carbonate-based electrolytes will inevitably lead to a sharp decrease in the capacity of SIBs. Herein, we design a carboxylate ester-based electrolyte with excellent ultra-low temperature performance by straightforward cosolvent strategy. Due to the low viscosity, melting point, and sufficient ionic conductivity of the designed electrolyte, the resulting Na||Na 3 V 2 (PO 4 ) 2 O 2 F can achieve the capacity retention of 96% (100 cycles at 0.1 C) at -40 degrees C and can also operate stably even at -50 degrees C. Besides, galvanostatic intermittent titration technique (GITT), ex-situ X-ray photoelectron spectroscopy (XPS), and high-resolution transmission electron microscopy (TEM) tests are employed to analyze and confirm that the carboxylate ester-based electrolyte promotes robust and uniform cathode/electrolyte interface layer formation and accelerates ion diffusion kinetics, which collectively facilitates the better low-temperature performance. In addition, the assembled hard carbon||NVPOF full cells further prove the practicability of the carboxylate ester-based electrolyte at low-temperature, which delivers high discharge capacity of 108.4 and 73.0 mAh g -1 at -25 and -40 degrees C. This work affords a new avenue for designing advanced low-temperature electrolytes for SIBs. (c) 2023 Published by Elsevier Ltd on behalf of The editorial office of Journal of Materials Science & Technology.

As a sodium superionic conductor, Mn‐rich phosphate of Na 3.4 Mn 1.2 Ti 0.8 (PO 4 ) 3 is considered as one of the promising cathodes for sodium‐ion batteries owing to its good thermodynamic stability and high working voltage. However, Na 3.4 Mn 1.2 Ti 0.8 (PO 4 ) 3 is faced with low electronic conductivity, poor cycling stability and complex phase transition caused by multi‐electron transfers, which limits its practical application. Herein, an anion‐regulated strategy is proposed to optimize the Mn‐rich Na 3.4 Mn 1.2 Ti 0.8 (PO 4 ) 3 phosphate cathode. After introducing F anions into the lattice, the rate performance is improved from 60.5 to 72.8 mAh g −1 at 20 C. Ascribed to unique structure design, the reaction kinetics of Na 3.4 Mn 1.2 Ti 0.8 (PO 4 ) 3 are significantly improved, as demonstrated by cyclic voltammetry at varied scan rates and galvanostatic intermittent titration technique. The generated M‐F bond inhibits Jahn–Teller effect with an improved cycle stability (85.8 mAh g −1 after 1000 cycles at 5 C with 94.3% capacity retention). Interestingly, reaction mechanism of Na 3.4 Mn 1.2 Ti 0.8 (PO 4 ) 3 with the complex two‐phase and solid solution reactions changes to the whole solid solution reaction after fluorine substitution, and leads to a smaller volume change of 5.41% during reaction processes, which is verified by in situ X‐ray diffraction. This anion regulation strategy provides a new method for designing the high‐performance phosphate cathode materials of sodium‐ion batteries.

Herein, a novel self-supporting three-dimensional nanostructured CoNi LDH-Ni3S2 catalyst was generated in a two-step process combining hydrothermal synthesis and high-temperature electrodeposition techniques. The CoNi LDH-Ni3S2/NF electrode exhibits superior electrocatalytic performance with low overpotentials of 193 and 382 mV in 1 M KOH to drive a high current density of 100 mA cm(-2) for HER and OER, respectively. Meanwhile, a small cell voltage of 1.51 V was obtained upon using CoNi LDH-Ni3S2/NF as a dual-functional catalyst. Additionally, CoNi LDH-Ni3S2/NF exhibits high stability with almost no change in HER and OER overpotentials and electrocatalytic total decomposition of water within 80,000 s.

峥嵘岁月奥运梦,华夏复兴双奥城.本文将"2008年北京夏季奥运会"与"2022年北京冬奥会"中的建筑材料拟人化,以座谈会的形式,通过第一人称的视角向读者介绍了夏、冬两届中国奥运会中"水立方""鸟巢"和"冰丝带"等经典奥运建筑中所运用的ETFE、PTFE和PVB三类有机化学材料,并讨论了它们的分子结构组成、性质以及在奥运建筑中所发挥的重要作用.

In this study, Sb0.7Bi0.3PS4 exhibits enhanced Na-storage performance through Bi3+ substitution. This ion substitution provides a strategy for advanced thiophosphate anodes in sodium-ion batteries.

Since the catalytic activity of present nickel-based synthetic selenide is still to be improved, MoSe2-Ni3Se2 was synthesized on nickel foam (NF) (MoSe2-Ni3Se2/NF) by introducing a molybdenum source. After the molybdenum source was introduced, the surface of the catalyst changed from a single-phase structure to a multi-phase structure. The catalyst surface with enriched active sites and the synergistic effect of MoSe2 and Ni3Se2 together enhance the hydrogen evolution reactions (HER), the oxygen evolution reactions (OER), and electrocatalytic total water splitting activity of the catalyst. The overpotential of the MoSe2-Ni3Se2/NF electrocatalyst is only 259 mV and 395 mV at a current density of 100 mA/cm2 for HER and OER, respectively. MoSe2-Ni3Se2/NF with a two-electrode system attains a current density of 10 mA/cm2 at 1.60 V. In addition, the overpotential of HER and OER of MoSe2-Ni3Se2/NF within 80000 s and the decomposition voltage of electrocatalytic total water decomposition hardly changed, showing an extremely strong stability. The improvement of MoSe2-Ni3Se2/NF catalytic activity is attributed to the establishment of the multi-phase structure and the optimized inoculation of the multi-component and multi-interface.

电化学储能设备已经成为现代社会不可分割的一部分.其中,锂离子电池(LIBs)的应用最为广泛.然而,地壳中锂资源短缺且分布不均匀,带来的较高成本和发展不均衡,急需研发其他高性能的二次电池.钠元素在地壳中储量均匀、丰富,并且具有与锂相似的化学性质,使得钠离子电池(SIBs)成为了代替LIBs最有应用前景的二次电池之一.SIBs中硫酸盐正极材料具有价格低廉和工作电位适中等优势,引发了研究者们的广泛关注,是极具潜力的新一代SIBs材料.本文总结了 SIBs硫酸盐正极材料的研究进展,主要介绍了硫酸盐材料的合成方法、晶体结构以及电化学性能,并分析了该类材料面临的主要问题和发展前景.