Porous TiO2(B)/anatase microspheres with hierarchical nano and microstructures for high-performance lithium-ion batteries
Porous TiO2(B)/anatase microspheres with hierarchical nano and microstructures for high-performance lithium-ion batteries
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DOI：
10.1016/j.electacta.2013.03.015
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发表时间：
2013-05
影响因子：
6.6
通讯作者：
Jie Wang;Yingke Zhou;Zongping Shao
中科院分区：
文献类型：
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作者：
Jie Wang;Yingke Zhou;Zongping Shao
采用溶剂热法制备了一种新型多级多孔TiO 2（B）/TiO 2微球，并对其作为锂离子电池负极材料的性能进行了评价。所制备的多孔微球直径在2.5 ~ 5.5μm之间，由横向尺寸为几微米、厚度约为13 nm的多孔TiO 2纳米片组装而成，而纳米片则由纳米级TiO 2微晶（约5- 7 nm）聚集而成。通过BET测试结果验证了分级多孔结构，具有典型的IV型等温曲线，高表面积（~186.2m2g-1）和两种孔（~4和8.3nm）。多级多孔TiO 2微球具有优异的电化学性能，具有较高的储锂容量和优异的高倍率循环性能（4500次循环后，在4000 mAg-1的速率下，比容量为117 mAhg-1），这可能归因于由分级微结构、TiO 2（B）/TiO 2异质结诱导的增强的Li+扩散和电子导电性，和TiO 2的赝电容（B）。这种分级多孔材料可能在先进的动力型锂离子电池中有应用前景。
Novel hierarchical porous TiO2(B)/anatase microspheres have been prepared by a facile solvothermal approach and evaluated as anode materials for advanced lithium-ion battery applications. The obtained porous microspheres, with diameters ranging from 2.5 to 5.5μm, are assembled by porous TiO2nanosheets with the lateral size of a few micrometers and thickness of ~13nm; whilst, the nanosheets are formed by aggregations of nanosized primary TiO2crystallites (~5–7nm). The hierarchical porous structures are verified by BET test results with a typical type-IV isotherm curve, a high surface area (~186.2m2g−1) and two kinds of pores (~4 and 8.3nm). The hierarchical porous TiO2microspheres present excellent electrochemical performance with high Li storage capacity and excellent high-rate cycling capability (a specific capacity of 117mAhg−1at the rate of 4000mAg−1after 4500 cycles), which might be attributed to the enhanced Li+diffusion and electronic conductivity induced by the hierarchical microstructures, the TiO2(B)/anatase heterojunction, and the pseudocapacitance of TiO2(B). Such hierarchical porous materials might be promising for applications in advanced power type lithium-ion batteries.