Aqueous zinc-sulfur batteries are a high-capacity and cost-effective energy storage technology. However, the performance is plagued by the dissolution of intermediate polysulfides formed during conversion. Here, this issue is addressed by developing aqueous rechargeable Zn-sulfurized polyacrylonitrile (SPAN) batteries using tandem catalytic systems, containing water and tetraglyme (G4) with iodine (I) additives.
View Article and Find Full Text PDFShuttling of lithium polysulfides and slow redox kinetics seriously limit the rate and cycling performance of lithium-sulfur batteries. In this study, FeO-dopped carbon cubosomes with a plumber's nightmare structure (SP-FeO-C) are prepared as sulfur hosts to construct cathodes with high rate capability and long cycling life for Li-S batteries. Their three-dimensional continuous mesochannels and carbon frameworks, along with the uniformly distributed FeO particles, enable smooth mass/electron transport, strong polysulfides capture capability, and fast catalytic conversion of the sulfur species.
View Article and Find Full Text PDFThe kinetics difference among multistep electrochemical processes leads to the accumulation of soluble polysulfides and thus shuttle effect in lithium-sulfur (Li-S) batteries. While the interaction between catalysts and representative species has been reported, the root of the kinetics difference, interaction change among redox reactions, remains unclear, which significantly impedes the catalysts design for Li-S batteries. Here, this work deciphers the interaction change among electrocatalytic sulfur reactions, using tungsten disulfide (WS ) a model system to demonstrate the efficiency of modifying electrocatalytic selectivity via dual-coordination design.
View Article and Find Full Text PDFLithium-sulfur (Li-S) batteries suffer from sluggish kinetics due to the poor conductivity of sulfur cathodes and polysulfide shutting. Current studies on sulfur redox catalysis mainly focus on the adsorption and catalytic conversion of lithium polysulfides but ignore the modulation of the electronic structure of the catalysts which involves spin-related charge transfer and orbital interactions. In this work, bimetallic phosphorus trisulfides embedded in Prussian blue analogue-derived nitrogen-doped hollow carbon nanocubes (FeCoPS/NCs) were elaborately synthesized as a host to reveal the relationship between the catalytic activity and the spin state configuration for Li-S batteries.
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