Efficient microwave hydrothermal synthesis of nanocrystalline orthorhombic LiMnO2 cathodes for lithium batteries
Efficient microwave hydrothermal synthesis of nanocrystalline orthorhombic LiMnO2 cathodes for lithium batteries
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DOI：
10.1016/j.electacta.2010.01.010
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发表时间：
2010-03-30
影响因子：
6.6
通讯作者：
Hong, Anqin
中科院分区：
文献类型：
--
作者：
Ji, Hongmei;Yang, Gang;Hong, Anqin
采用温控微波水热法（TCMH），在160 ℃的低温下，在短时间（30 min）内成功合成了棒状正交LiMnO 2纳米晶。采用X射线衍射（XRD）、扫描电子显微镜（SEM）和电化学测试对两种方法制备的o-LiMnO 2进行了表征。SEM显示，TCMH法制备的产物为直径为40 nm的棒状，而传统水热法制备的产物为直径为200 nm的纳米粒子。在微波水热场中，o-LiMnO 2的大量生成影响了最终产物的形貌和晶体结构。讨论了微波辐照过程中o-LiMnO 2的形成和择优生长机理。电化学性能测试表明，所合成的o-LiMnO 2纳米棒在室温下于2.2 ~ 4.4V vs. Li+/Li之间循环几次后，在0.1C倍率下的最大放电容量达到194.2mAh g（-1），高于TH法制备的o-LiMnO 2的电化学性能。实验结果表明，TCMH法为锂离子电池正极材料o-LiMnO 2的制备提供了一条有效的途径。(C)2010爱思唯尔有限公司版权所有。
Rod-like orthorhombic LiMnO2 nanocrystals were successfully synthesized using temperature-controlled microwave hydrothermal route (TCMH) in a short time (30 min) at a temperature as low as 160 degrees C. o-LiMnO2 obtained by two different methods was characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM) and electrochemistry test. SEM revealed that the product obtained in case of TCMH was rod-like with a diameter of 40 nm, while the nanoparticles with 200 nm diameter were obtained by traditional hydrothermal route (TH). The dramatic formation of o-LiMnO2 in the microwave hydrothermal field influenced the morphology and crystal structure of the final products. The formation and preferred growth orientation mechanism of o-LiMnO2 in the microwave irradiation process was discussed. Electrochemistry performance exhibited that the as-synthesized o-LiMnO2 nanorods reached the maximum discharge capacity of 194.2 mAh g(-1) at 0.1 C rate after several cycles between 2.2 and 4.4V vs. Li+/Li at room temperature, which was higher than the electrochemical performance of o-LiMnO2 obtained by TH. The experimental results showed that the TCMH method provided an effective way for preparing o-LiMnO2 cathode material in lithium-ion batteries. (C) 2010 Elsevier Ltd. All rights reserved.