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High-performance lithium–sulfur (Li–S) batteries that can work normally under harsh conditions have attracted tremendous attention; however, the sluggish reaction kinetics of polysulfide conversions at low temperatures as well as the notorious polysulfide shuttling at high temperatures remain to be resolved. Herein, a multibranched vanadium nitride (MB-VN) electrocatalyst has been designed and deployed for Li–S batteries. Both experimental (time-of-flight secondary ion mass spectroscopy and adsorption tests) and theoretical results verify the strong chemical adsorption capability and high electrocatalytic activity of MB-VN with respect to polysulfides. Moreover, in situ Raman characterization manifests the effective inhibition of polysulfide shuttling by the MB-VN electrocatalyst. Using MB-VN-modified separators, the Li–S batteries deliver an excellent rate capability (707 mAh g–1 at 3.0 C) and great cyclic stability (678 mAh g–1 after 400 cycles at 1.0 C) at room temperature. With 6.0 mg cm–2 of sulfur and a lean electrolyte volume of ∼6 μL mgs–1, Li–S batteries exhibit a high areal capacity of 5.47 mAh cm–2. Even over a wide temperature range (−20 to +60 °C), the Li–S batteries still maintain stable cyclic performance at high current rates. This work demonstrates that metal nitride based electrocatalysts can realize low-/high-temperature-tolerant Li–S batteries.
Ma et al. (Thu,) studied this question.