Thermal formation of mesoporous single-crystal Co3O4 nano-needles and their lithium storage properties
Thermal formation of mesoporous single-crystal Co3O4 nano-needles and their lithium storage properties
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DOI：
10.1039/b810093d
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发表时间：
2008-01-01
影响因子：
--
通讯作者：
Archer, Lynden A.
中科院分区：
文献类型：
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作者：
Lou, Xiong Wen (David);Deng, Da;Archer, Lynden A.
在这项工作中，我们报告了具有三维单晶框架的介孔Co3O4纳米针的简单固态形成。该合成基于前驱体b-Co(OH)(2)纳米针的受控热氧化分解和再结晶。重要的是，经过热处理后，针状形态可以完全保留，尽管在此过程中存在较大的体积收缩：β - co (OH)(2)/Co3O4。由于晶体固有的收缩，同时产生了具有高比表面积的高介孔结构。通过在200-400℃之间改变退火温度，可以很容易地定制文本特性。有趣的是，在更高温度下的热再结晶可以形成完美的3D单晶框架。由此衍生的介孔Co3O4纳米针可作为研究锂存储性能的良好模型体系。优化后的样品具有非常低的初始不可逆损耗（21%）、超高容量和优异的循环性能。例如，在50次循环后可以保持1079 mA h g（-1）的可逆容量。其优异的电化学性能和易于合成的特性可能表明其在锂离子电池中的实际应用。
In this work, we report the simple solid-state formation of mesoporous Co3O4 nano-needles with a 3D single-crystalline framework. The synthesis is based on controlled thermal oxidative decomposition and re-crystallization of precursor b-Co(OH)(2) nano-needles. Importantly, after thermal treatment, the needle-like morphology can be completely preserved, despite the fact that there is a large volume contraction accompanying the process: beta-Co(OH)(2)/Co3O4. Because of the intrinsic crystal contraction, a highly mesoporous structure with high specific surface area has been simultaneously created. The textual properties can be easily tailored by varying the annealing temperature between 200-400 degrees C. Interestingly, thermal re-crystallization at higher temperatures leads to the formation of a perfect 3D single-crystalline framework. Thus derived mesoporous Co3O4 nano-needles serve as a good model system for the study of lithium storage properties. The optimized sample manifests very low initial irreversible loss (21%), ultrahigh capacity, and excellent cycling performance. For example, a reversible capacity of 1079 mA h g(-1) can be maintained after 50 cycles. The superior electrochemical performance and ease of synthesis may suggest their practical use in lithium-ion batteries.