Superior high-rate lithium-ion storage on Ti2Nb10O29 arrays via synergistic TiC/C skeleton and N-doped carbon shell
Superior high-rate lithium-ion storage on Ti2Nb10O29 arrays via synergistic TiC/C skeleton and N-doped carbon shell
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DOI：
10.1016/j.nanoen.2018.10.024
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发表时间：
2018-12
期刊：
影响因子：
17.6
通讯作者：
Z. Yao;X. Xia;Yan Zhang;D. Xie;Changzhi Ai;Shiwei Lin;Yadong Wang;Shengjue Deng;Shenghui Shen-Sh
中科院分区：
文献类型：
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作者：
Z. Yao;X. Xia;Yan Zhang;D. Xie;Changzhi Ai;Shiwei Lin;Yadong Wang;Shengjue Deng;Shenghui Shen-Sh
高倍率负极的定向构建对于下一代大功率锂离子电池的发展具有重要意义。在目前的工作中，我们报告了一个强大的组合策略，智能构建全方位的导电网络组成的TiC/C阵列的核心和N-掺杂的碳（NC）壳夹心Ti 2Nb 10 O29（TNO）纳米粒子形成集成NC-TNO@TiC/C核/壳阵列。DFT结果表明，TiC/C阵列骨架具有良好的电子导电性和高刚性，而N掺杂碳层有利于Li离子的电子/离子输运动力学，从而降低了Li离子的能垒。因此，NC-TNO@TiC/C电极显示出优异的高倍率容量（1 C时为318 mA h g− 1，50 C时为202 mA h g− 1），循环寿命长，在10 C下循环10，000次后容量保持率为85%，由于导电NC外层和TiC/TiO 2对增强的离子/电子转移和增强的结构的正协同效应，C骨架。由NC-TNO@TiC/C阳极和LiFePO 4（LFP）阴极组装的全电池也表现出优异的电化学性能，具有良好的应用前景。这种多元结构设计可为其他储能器件的混合高倍率电极的制备提供指导。
Directional construction of high-rate anode is of great importance for the development of next-generation large-power lithium ion batteries. In the present work, we report a powerful combined strategy for smart construction of omnibearing conductive networks composed of TiC/C arrays core and N-doped carbon (NC) shell to sandwich Ti2Nb10O29(TNO) nanoparticles forming integrated NC-TNO@TiC/C core/shell arrays. Except for good electronic conductivity and high rigidity from TiC/C arrays skeleton, lower energy barrier of Li ion is obtained via the N-doped carbon layer facilitating the ion/electron transport kinetics according to DFT results. Accordingly, the NC-TNO@TiC/C electrode shows preeminent high-rate capacities (318 mA h g−1at 1 C and 202 mA h g−1at 50 C) and a long cycle life with a capacity retention of 85% after 10,000 cycles at 10 C, better than other TNO counterpart due to the positive synergistic effect on enhanced ion/electron transfer and reinforced structure from conductive NC outer layer and TiC/C skeleton. The full cell assembled by NC-TNO@TiC/C anode and LiFePO4(LFP) cathode also shows excellent electrochemical properties with promising application prospect. This polybasic structure design could offer guidelines for fabrication of other hybrid high-rate electrodes for energy storage devices.