Room temperature sodium-sulfur (RT Na-S) batteries attract many attentions since they endow many overwhelming merits, for instances, resources abundances of S and Na, high theoretical capacity of S (1672 mAh g-1), non-toxicity, and cost-efficiency. Nevertheless, the Na-S batteries are often restrained for their poor cycling performance and inferior Coulombic efficiency, which result from the sodium polysulfide (NaPSs) dissolution and the sluggish kinetics reactions. These issues always result in fast active materials loss and rapid cycling decay. To overcome these challenges, preventing the reactions between NaPSs species on the cathode, long-chain NaPSs dissolution and improving the kinetics reaction are extremely important. Therefore, it is very important to prepare the novel hosts with proper pore structure and enough surface area to embed the active materials and provide enough volume for S expansion during the cell working. Moreover, by decoration of abundant electrocatalytic acti
Room temperature sodium sulfur (RT Na-S) batteries with high theoretical energy density and low cost have recently gained extensive attention for potential large-scale energy storage applications. However, the shuttle effect of sodium polysulfides is still the main challenge that leads to poor cycling stability, which hinders the practical application of RT Na-S batteries. Herein, a multifunctional hybrid MXene interlayer is designed to stabilize the cycling performance of RT Na-S batteries. The hybrid MXene interlayer comprises a large-sized Ti3C2Tx nanosheets inner layer followed by a small-sized Mo2Ti2C3Tx nanoflake outer layer on the surface of the glass fiber (GF) separator. The large-sized Ti3C2Tx nanosheet inner layer provides an effective physical block and chemical confinement for the soluble polysulfides. The small-sized Mo2Ti2C3Tx outer layer offers an excellent polysulfide trapping capability and accelerates the reaction kinetics of polysulfide conversion, due to its superi
The cathode materials for sodium-sulfur batteries have attracted great attention since cathode is one of the important components of the sodium-sulfur battery, and there are cathode materials that have high capacity, non-toxicity, and cost-efficiency. Nevertheless, due to their low Coulombic efficiency and proneness to cycling decay, the practical application of the sodium–sulfur battery has always been suppressed. In terms of the responsibility of these problems, the polysulfide shuttle and the sluggish kinetics are the main culprits. To address these issues, impeding the notorious reaction between polysulfide intermediates on the cathode and improve the kinetics reaction on the anode are extremely important. Herein, a comprehensive review is prepared of different approaches to increasing the electrochemical performance and strengthening the stability of cathodes. The influences of various choices and the consequent properties of the cathode in relation to the whole sodium–sulfur
Advanced Na-SexSy batteries provide a good chance to take full advantage of rich Na resources in the earth's crust as well as to combine the high capacity of S with the high electronic conductivity of Se, which are expected to become a new high-energy density electrochemical energy storage system. Herein, we offer a comprehensive review of recent advances in advanced Na-SexSy battery system with a focus on fundamental insights into its chemistry, materials design, and potential improvement strategies. Firstly, the electrochemical mechanisms of Na-SexSy batteries are presented to deepen the understanding of electrochemical principle. Then, the main challenges facing such a new system are summarized, encompassing low reactivity of SexSy with a low Se ratio, shuttle effect of intermediates, large volumetric variation, and sodium dendritic growth., Next, we discuss the design strategies of cathode materials for Na-SexSy batteries in detail, involving their synthesis, properties, inter
A facile and general vacuum-filtration approach is employed to coat hierarchical metal–organic framework-derived Co-C polyhedrons onto traditional separators for lithium − sulfur batteries. The resultant condensed separators with Co-C coating (Co-C@separator) can effectively decrease the pore size of commercial separators from 200 to 300 nm to 2.2–10 nm. The decreased pore sizes block the shuttling of lithium polysulfides (LiPSs) through the separator, thus solving the annoying ‘shuttle effect’ via physical confinement. Furthermore, the embedded Co nano-nodes in Co-C polyhedrons are capable of capturing LiPSs via strong chemical adsorption of soluble LiPSs. Through this advantage combined with the rapid Li-ion transport through the intragranular pores between the Co-C polyhedrons, a sulfur-rich cathode (72% sulfur) has achieved outstanding performance when using the Co-C@separator, delivering decent cycling stability (675 mAh g after 300 cycles at 0.1 A g ) and high rate per