Aiming to accelerate sodium-ion transport kinetics and improve electrochemical cyclability of batteries, an In₂S₃/CoS₂ bimetallic sulfide heterostructure was synthesized as anodes of sodium-ion batteries (SIBs) in this paper by a feasible ion exchange and subsequent hydrothermal vulcanization technique based on a cobalt metal-organic skeleton (ZIF-67) precursor. As-prepared In₂S₃/CoS₂ composite exhibited an excellent rate capability of 453.8 mAh g^-1 at 10 A g^-1 and outstanding cyclability of 464.06 mAh g^-1 after 600 cycles at 2 A g^-1. The built-in electric filed between heterogeneous interface of In₂S₃ and CoS₂ plays a dominant contribution on improvement of electronic conductivity and charge transfer kinetics. Beyond that abundant defects derived from ion exchange and nanocrystallization of composite particles also have a positive synergistic effect on inducing additional active centers for adsorption of Na⁺ and shortening ion transport distance for further accelerating reaction kinetics. Based on exploring conversion and alloying mechanism of In₂S₃/CoS₂ composite via ex situ XRD and TEM, high-performance SIBs with heterostructure bimetallic sulfide anodes may be a prospective strategy.

中文翻译：

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富含缺陷的 In2S3/CoS2 异质结构，用于钠离子的快速储存


为了加速钠离子传输动力学并提高电池的电化学可循环性，本文通过可行的离子交换和随后的基于钴金属有机骨架 （ZIF-67） 前驱体的水热硫化技术合成了 In₂S₃/CoS₂ 双金属硫化物异质结构作为钠离子电池 （SIB） 的负极。制备的 In₂S₃/CoS₂ 复合材料在 10 A ^g-1 下表现出 453.8 mAh ^g-1 的出色倍率能力，在 2 A ^g-1 下循环 600 次后，表现出 464.06 mAh ^g-1 的出色循环性。In₂S₃ 和 CoS₂ 异质界面之间的内置电场对提高电子电导率和电荷转移动力学起着重要贡献。除此之外，离子交换和复合颗粒纳米化衍生的大量缺陷也对诱导额外的活性中心吸附 Na⁺ 和缩短离子传输距离以进一步加速反应动力学具有积极的协同作用。基于通过非原位 XRD 和 TEM 探索 In₂S₃/CoS₂ 复合材料的转化和合金化机制，具有异质结构双金属硫化物阳极的高性能 SIB 可能是一种前瞻性策略。