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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]

Room‐temperature Na–S batteries are facing one of the most serious challenges of charge/discharge with long cycling stability due to the severe shuttle effect and volume expansion. Herein, a sodium polysulfides defense system is presented by designing and constructing the cathode‐separator double barriers. In this strategy, the hollow carbon spheres are decorated with MoS2 (HCS/MoS2) as the S carrier (S@HCS/MoS2). Meanwhile, the HCS/MoS2 composite is uniformly coated on the surface of the glass fiber as the separator. During the discharge process, the MoS2 can adsorb soluble polysulfides (NaPSs) intermediates and the hollow carbon spheres can improve the conductivity of S as well as act as the reservoir for electrolyte and NaPSs, inhibiting them from entering the anode to make Na deteriorate. As a result, the cathode‐separator group applied to room‐temperature Na–S battery can enable a capacity of ≈1309 mAh g−1 at 0.1 C and long cycling life up to 1000 cycles at 1 C. This study provides a novel and effective way to develop durable room‐temperature Na–S batteries. [ABSTRACT FROM AUTHOR]