Abstract Deficiencies of sulfur cathode including polysulfide shuttling and poor redox kinetics severely limit cycling performance of lithium-sulfur (Li-S) batteries. Herein, we have designed a binary host featuring highly sulfiphilic Ni-Fe bimetallic oxide (NiFe2O4) nanoparticles anchored on carbon nanotubes for Li-S batteries. NiFe2O4 nanoparticles provide highly sulfiphilic sites to confine lithium polysulfides by the formation of Li-O and S-O bonds, and act as an electrocatalyst to promote the conversion of polysulfides. The carbon nanotubes play an important synergistic role by providing efficient electron conduction pathways and preventing agglomeration of the catalyst. As a result, the sulfur cathode enables stable cycling with a very low capacity fade rate (∼0.029% per cycle upon 1000 cycles) at 1.0 C and a reversible capacity of ∼550 mAh g−1 at 5.0 C. Further, the superior cycling stability could be retained even for high sulfur loading of ∼5.0 mg cm−2. The development of such hybrid electrodes comprised of bimetallic oxides supported on carbon nanotubes could help realize long-lasting and stable Li–S batteries.

中文翻译：

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锚定在碳纳米管上的高亲硫性 Ni-Fe 双金属氧化物纳米粒子能够有效固定和转化多硫化物，从而实现稳定的锂硫电池

摘要 硫正极的缺陷包括多硫化物穿梭和氧化还原动力学差，严重限制了锂硫（Li-S）电池的循环性能。在此，我们设计了一种二元主体，其特征在于高度亲硫性的 Ni-Fe 双金属氧化物 (NiFe2O4) 纳米颗粒固定在用于 Li-S 电池的碳纳米管上。NiFe2O4 纳米颗粒通过形成 Li-O 和 SO 键提供高度亲硫性的位点来限制多硫化锂，并作为电催化剂促进多硫化物的转化。碳纳米管通过提供有效的电子传导途径和防止催化剂团聚而发挥重要的协同作用。因此，硫正极能够以非常低的容量衰减率（1000 次循环后每循环约 0.029%）在 1. 0 C和5.0 C下~550 mAh g-1的可逆容量。此外，即使在~5.0 mg cm-2的高硫负载下也能保持优异的循环稳定性。这种由碳纳米管上负载的双金属氧化物组成的混合电极的开发有助于实现持久且稳定的锂硫电池。