Structure-designed synthesis of yolk-shell hollow ZnFe2O4/C@N-doped carbon sub-microspheres as a competitive anode for high-performance Li-ion batteries
Structure-designed synthesis of yolk-shell hollow ZnFe2O4/C@N-doped carbon sub-microspheres as a competitive anode for high-performance Li-ion batteries
复制标题
结构设计合成蛋黄壳空心 ZnFe2O4/C@N 掺杂碳亚微球作为高性能锂离子电池的竞争性负极
DOI：
10.1039/c8ta04347g
复制
发表时间：
2018-10-07
影响因子：
11.9
通讯作者：
Yuan, Changzhou
中科院分区：
文献类型：
--
作者：
Hou, Linrui;Bao, Ruidi;Yuan, Changzhou
尖晶石型ZnFe_2 O_4（ZFO）由于其固有的优点，近年来成为锂离子电池（LIB）的一种引人注目的负极材料。然而，严重的电极粉化和低的导电性极大地阻碍了其商业应用。在此，我们描述了多功能蛋黄-壳中空结构的有意制造，命名为H-ZFO-C（避免@C），其中具有内部均匀分布的碳网络的中空ZFO亚微球以无模板的方式制备为蛋黄，沿着具有导电的N掺杂的碳纳米壳和功能性空隙间隙。结构/几何模拟和实验证实，蛋黄的良好定义的内部空隙和中空内部可以有效地适应锂化的体积膨胀，而不会破坏外部纳米壳，同时确保良好的蛋黄-壳电子接触和外表面上薄而稳定的固体电解质界面膜。导电的纳米碳壳和连续的内部碳网络防止纳米ZFO亚基的严重聚集，并在重复的锂化/脱锂过程中促进方便的电荷转移。受益于这些吸引人的设计原理的协同贡献，我们的集成H-ZFO-C@void@C阳极提供了类似于76.8%的高初始库仑效率，在2000 mA g（-1）下类似于775 mA h g（-1）的显著可逆容量，以及在1000 mA g（-1）的高速率下500次循环后的长期循环能力。更有希望的是，我们的设计为先进的LIB提供了具有竞争力的金属氧化物阳极结构。
Spinel ZnFe2O4(ZFO) has recently gained prominence as a fascinating anode for lithium-ion batteries (LIBs) owing to its intrinsic merits. However, serious electrode pulverization and modest electrical conductivity hugely hinder its commercial application. Herein, we describe the deliberate fabrication of a multi-functional yolk-shell hollow architecture, designated as H-ZFO-C(avoid@C, where hollow ZFO sub-microspheres with an internal well-distributed carbon network were prepared in a template-free manner as a yolk, along with a conductive N-doped carbon nanoshell and functional void interspace. Structural/ geometric simulations and experiments confirm that the well-defined internal void and hollow interior of the yolk can efficiently accommodate volumetric expansion over lithiation without breaking the outer nanoshell while ensuring good yolk-shell electronic contact and a thin yet stable solid-electrolyteinterphase film on the outer surface. The conducting nano-carbon shell and continuous internal carbon network prevent the serious aggregation of nano-ZFO subunits, and facilitate convenient charge transfer during repeated lithiation/delithiation processes. Benefiting from the synergetic contributions of these appealing design rationales, our integrated H-ZFO-C@void@C anode delivers a high initial coulombic efficiency of similar to 76.8%, a remarkable reversible capacity of similar to 775 mA h g(-1) at 2000 mA g(-1), and long-term cyclability after 500 cycles at a high rate of 1000 mA g(-1). More promisingly, our design here offers a competitive metal oxide-based anode structure for advanced LIBs.