Rapid activation and enhanced cycling stability of Co3O4 microspheres decorated by N-doped amorphous carbon shell for advanced LIBs
Rapid activation and enhanced cycling stability of Co3O4 microspheres decorated by N-doped amorphous carbon shell for advanced LIBs
复制标题
用于先进LIB的N掺杂非晶碳壳修饰的Co3O4微球的快速活化和增强的循环稳定性
DOI：
10.1016/j.electacta.2018.07.021
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发表时间：
2018-09-01
影响因子：
6.6
通讯作者：
Li, Junshuai
中科院分区：
文献类型：
--
作者：
Liu, Mengting;Hou, Xiaoyi;Li, Junshuai
Co3O4具有理论容量高、成本低等优点，一直是锂离子电池负极材料的研究热点。然而，循环过程中固有的结构粉化和活化滞后严重限制了其实际应用。为了克服这一局限性，本工作成功地探索了一种简便的方法，即在多巴胺-三胺(DA-TRIS)溶液中注入空气，然后在Ar气氛中进行热处理，以在Co3O4微球表面修饰N掺杂的非晶态碳(a-C)壳层。N掺杂的a-C壳层由N掺杂的a-C薄膜和纳米颗粒共同构成。DA-Tris的浓度对N掺杂a-C壳层的结构性质和Co3O4微球的相结构有重要影响。作为LiBS的负极材料，由N掺杂a-C壳层修饰的Co3O4微球在500 mag(-1)和1000 mag(-1)下分别表现出1074mAhg(-1)和830mAhg(-1)的优异的可逆性能。此外，其倍率容量令人印象深刻，活化滞后现象得到有效缓解。如此优异的锂离子存储性能首先归功于金属Co促进Co3O4的快速活化，而N掺杂的a-C壳层原位还原了Co3O4的活化。其次，N掺杂的a-C壳层有效地防止了结构的破裂，促进了Co3O4微球的电化学反应。这项工作为缓冲用于高级LiBS应用的过渡金属氧化物的活化滞后提供了一种有效的方法。(C)2018爱思唯尔有限公司。保留所有权利。
Co3O4 has been always highlighted as an anode material for lithium ion batteries (LIBs) due to its high theoretical capacity and low cost. However, its practical application is severely limited by the inherent structural pulverization and activation hysteresis during cycling. To overcome such limitation, in this work, a facile route of air-injection assisted soaking in dopamine-tris (DA-tris) solution followed by annealing in Ar atmosphere is successfully approached to decorate N-doped amorphous carbon (a-C) shells on surface of Co3O4 microspheres. The N-doped a-C shells are co-constructed by films and nanoparticles of N-doped a-C. The concentration of DA-tris plays significant roles to the structural nature of the N-doped a-C shells and the phase configuration of the Co3O4 microspheres. As an anode material for LIBs, the Co3O4 microspheres decorated by the N-doped a-C shells exhibit superior reversible capabilities of 1074 mAhg(-1) under 500 mAg(-1) and 830mAhg(-1) under 1000 mAg(-1) after 500 cycles, respectively. Moreover, the rate capacity is impressive and the activation hysteresis is remitted effectively. Such an excellent lithium ions storage performance is firstly ascribed to the rapid activation of Co3O4 promoted by metallic Co, which is reduced by the N-doped a-C shells in situ. Secondly, the N-doped a-C shells effectively protect the structure from cracking and promote the electrochemical reactions of the Co3O4 microspheres. The present work provides an effective way to buffer the activation hysteresis of the transition metal oxides used for advanced LIBs application. (C) 2018 Elsevier Ltd. All rights reserved.