Enhanced capability and cyclability of flexible TiO2-reduced graphene oxide hybrid paper electrode by incorporating monodisperse anatase TiO2 quantum dots
Enhanced capability and cyclability of flexible TiO2-reduced graphene oxide hybrid paper electrode by incorporating monodisperse anatase TiO2 quantum dots
复制标题
通过结合单分散锐钛矿型 TiO2 量子点增强柔性 TiO2 还原氧化石墨烯混合纸电极的性能和循环性能
DOI：
10.1016/j.electacta.2017.10.129
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发表时间：
2018
影响因子：
6.6
通讯作者：
Zhang Haiyan
中科院分区：
文献类型：
--
作者：
Li Yunyong;Huang Ying;Ou Changzhi;Zhu Junlu;Yuan Xingxing;Yan Liang;Li Wenwu;Zhang Haiyan
将金属氧化物纳米颗粒作为电化学活性第二相引入到纸状柔性石墨烯基混合电极中。其尺寸和分散性是决定柔性混合纸电极的倍率性能和循环稳定性的关键因素。本文采用原位合成的超细单分散TiO 2量子点（QDs，约4. 0 nm）作为电化学活性第二相，通过简单的混合溶剂热反应和真空过滤将其均匀地引入柔性杂化纸中，旨在实现高倍率、长循环的柔性TiO 2基锂离子电池负极材料。通过结合超细TiO 2-QD和三维（3D）导电网络两者的优点，所制备的TiO 2-QD还原的氧化石墨烯（TiO 2-QDs-RGO）杂化纸电极在0.1 A g− 1下循环100次后显示出201 mA h g− 1的高可逆容量和优异的上级倍率性能，以及1500次循环的长循环寿命，其中1500次循环的循环寿命为80.6%。2.0 A g−1时的容量保持率。详细的电化学分析表明，杂化纸电极的性能和循环性能的提高是由于复合材料的嵌入和界面储锂行为以及三维快速电子/离子转移的结果，这归因于TiO 2-QD的超小尺寸和杂化纸电极的三维自支撑导电网络。结果表明，我们的材料设计策略具有明显的优势，也可能为进一步研究其他柔性金属氧化物/石墨烯混合纸电极在LIB中的快速和长寿命柔性阳极铺平道路。
Metal oxide nanoparticles as the electrochemically active second phase were incorporated into the paper-like flexible graphene-based hybrid electrodes. Its size and dispersion are crucial factors for determining the rate capability and cycling stability of the flexible hybrid paper electrode. Herein, we employin-situformed ultrafine monodisperse TiO2quantum dots (QDs, ∼4.0 nm) as the electrochemically active second phase, which are uniformly incorporated into the flexible hybrid paperviaa simple mixed solvothermal reaction together with a vacuum filtration, aiming at achieving a high-rate and long-cycle flexible TiO2-based anode in lithium ion batteries (LIBs). By combining the advantages of both ultrafine TiO2-QDs and three-dimensional (3D) conductive networks, the as-fabricated TiO2-QDs-reduced graphene oxide (TiO2-QDs-RGO) hybrid paper electrode shows high reversible capacity of 201 mA h g−1after 100 cycles at 0.1 A g−1and superior rate capability as well as long cycle life of 1500 cycles with ∼80.6% capacity retention at 2.0 A g−1. Detailed electrochemical analysis shows that the improved capability and cyclability of the hybrid paper electrode results from the integrated intercalation-based and interfacial lithium storage behaviors as well as the 3D fast electron/ion transfer of materials, which is ascribed to the ultra-small size of TiO2-QDs and the 3D self-standing conductive networks of the hybrid paper electrode. The results demonstrate the distinct advantages of our material design strategy, and also might pave the way for further studies of other flexible metal oxide/graphene hybrid paper electrodes for fast and long-life flexible anodes in LIBs.