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To obtain unbroken sulfides with delicate morphology from metal–organic frameworks (MOFs), a method for in situ growth of SiO2 protective layers on the surface of MOFs is proposed. This strategy can be successfully expanded to a variety of MOFs (ZIF‐67, Cu‐MOF, ZIF‐8, and PBA). Importantly, room‐temperature Na‐SeS2 batteries with Co9S8@SiO2/C prepared from ZIF‐67 as cathode host are assembled. Due to the hollow structure that can relieve the volume expansion and the co‐adsorption of sodium polysulfides/sodium polyselenides by Co9S8@SiO2/C, the SeS2/Co9S8@SiO2/C cathode shows excellent rate performance and Coulombic efficiency. In addition, ex situ X‐ray diffraction and in situ Raman results show that S8 and Se8 are generated after the discharge of SeS2, and Se8 is preferentially oxidized during charging. [ABSTRACT FROM AUTHOR]

The electrochemical performance of a material is largely impeded by the size and conductivity of the material. To overcome the defects, high-capacity nanoscale Bi2S3 particles and highly conductive Ti3C2Tx sheets have been composited and applied to sodium-ion batteries for the first time. The Bi2S3 nanoparticles are uniformly anchored on the MXene sheets, forming a sandwich-like stereochemical structure, which can alleviate the volume expansion and agglutination, reduce sodium ion migration path, and increase the active areas. Furthermore, the MXene nanosheets provide a conductive skeleton and accelerate the sodium ion and electron transition. Benefiting from the synergistic effect of the Bi2S3 nanoparticles on the MXene flakes, the Bi2S3/MXene composite exhibits excellent electrochemical properties for sodium-ion batteries. [ABSTRACT FROM AUTHOR]

Solid state sodium-ion batteries (SSIBs) are promising energy storage devices due to the advanced safety and abundant natural sodium sources. However, the developments of SSIBs are seriously limited by the shortage of choice for both solid state electrolytes and anode materials. To cater to this problem, we provide a composite of cobalt disulfide and carbon nanotubes grown in situ on MXene and a derivative grown out of MXene during the prepared process (named as CoS2/CNTs/TiOxNy) as an anode material, and PFSA-Na membranes as the solid-state electrolyte for SSIBs. The as-suggested SSIBs based on CoS2/CNTs/TiOxNy and PFSA-Na membranes demonstrate promising electrochemical properties under room temperature, which is a significant improvement compared with the high-temperature running SSIBs. Furthermore, the electrochemical mechanism of CoS2/CNTs/TiOxNy in the SSIBs was investigated by in situ Raman and ex situ XPS analyses to understand the reaction mechanism. [ABSTRACT FROM AUTHOR]

A solid‐state polymer electrolyte (PFSA‐Na membrane) for solid‐state sodium‐ion batteries (SSIBs) to overcome severe safety issues caused by traditional liquid electrolytes is explored. The PFSA‐Na membranes, synthesized by an environmentally and economically friendly method, display high ionic conductivity, excellent thermal stability, and outstanding mechanical flexibility in a wide temperature range. SSIBs based on the PFSA‐Na membranes and Prussian blue cathode exhibit a superior rate performance of 87.5 mA h g−1 at 8 C and a durable cycling life of up to 1100 cycles at 1 C with only a slight capacity decay of ≈0.014% per cycle. Furthermore, due to the intrinsic advantages of the PFSA‐Na membranes, the cyclic performance of the proposed SSIBs is more stable than that of its liquid counterpart even at the rather low temperature of −35 °C. [ABSTRACT FROM AUTHOR]

The stability of aqueous zinc metal batteries is significantly affected by side reactions and dendrite growth on the anode interface, which primarily originate from water and anions. Herein, we introduce a multi H-bond site additive, 2, 2'-Sulfonyldiethanol (SDE), into an aqueous electrolyte to construct a sieving-type electric double layer (EDL) by hydrogen bond interlock in order to address these issues. On the one hand, SDE replaces H2O and SO42- anions that are adsorbed on the zinc anode surface, expelling H2O/SO42- from the EDL and thereby reducing the content of H2O/SO42- at the interface. On the other hand, when Zn2+ are de-solvated at the interface during the plating, the strong hydrogen bond interaction between SDE and H2O/SO42- can trap H2O/SO42- from the EDL, further decreasing their content at the interface. This effectively sieves them out of the zinc anode interface and inhibits the side reactions. Moreover, the unique characteristics of trapped SO42- anions can restrict their diffusion, thereby enhancing the transference number of Zn2+ and promoting dendrite-free deposition and growth of Zn. Consequently, utilizing an SDE/ZnSO4 electrolyte enables excellent cycling stability in Zn//Zn symmetrical cells and Zn//MnO2 full cells with lifespans exceeding 3500 h and 2500 cycles respectively., (© 2024 Wiley‐VCH GmbH.)