CIESC Journal ›› 2019, Vol. 70 ›› Issue (7): 2775-2785.DOI: 10.11949/0438-1157.20190027

• Material science and engineering, nanotechnology • Previous Articles     Next Articles

Preparation of LiMn1-xMgxPO4/C cathode materials by microwave-assisted solvothermal method

Jihua ZHU(),Yao CHEN,Xiulian QIU,Yuming HUANG,Cheng ZHENG,Wei YANG()   

  1. School of Chemistry and Chemical Engineering, Guangzhou University, Guangzhou 510006, Guangdong, China
  • Received:2019-01-09 Revised:2019-04-16 Online:2019-07-05 Published:2019-07-05
  • Contact: Wei YANG

微波辅助溶剂热法制备LiMn1-xMgxPO4/C正极材料

朱计划(),陈姚,丘秀莲,黄宇明,郑成,杨伟()   

  1. 广州大学化学化工学院,广东 广州 510006
  • 通讯作者: 杨伟
  • 作者简介:朱计划(1992—),男,硕士研究生,<email>497691268@qq.com</email>
  • 基金资助:
    国家自然科学基金项目(21878058);广东省自然科学基金项目(2018A030313423)

Abstract:

Magnesium-doped lithium manganese phosphate(LiMn1-xMgxPO4/C) electrode materials were successfully prepared by microwave-assisted solvothermal synthesis. X-Ray diffraction, scanning electron microscope, thermogravimetry and Brunaur-Emmett-Teller method were employed to characterize crystal structures and morphology, and the electrochemical characteristics of the as-prepared materials were evaluated by galvanostatic charge/discharge, cyclic voltammetry and AC impedance method. The results showed that the plate-like LiMn1-xMgxPO4/C samples, which were synthesized from the microwave-assisted solvothermal method, possessed large specific surface area and well-defined mesoporous structure. In particular, Mg2+ doping exerts a significant effect on synthesizing flake-like nanocrystal which favors lithium-ion extraction/insertion reactions, improving the electrochemical activity and electrochemical performance of LiMnPO4/C material. As a result, the LiMn0.95Mg0.05PO4/C nanoparticle exhibited a high reversible capacity of 141.2 and 95.3 (mA·h)/g at 0.1 C and 5 C, respectively, exhibited outstanding charge/discharge performance and rate capability. Compared to conventional solvothermal synthetic route, microwave-assisted solvothermal approach led to a significant decrease in the reaction time and the as-prepared material possessed excellent electrochemical performance. It is extraordinary and remarkable for the preparation of high-performance LiMnPO4 cathode material, providing a new method for the preparation of electrode materials for Li-ion batteries.

Key words: microwave synthesis, lithium manganese phosphate, nanomaterials, electrochemistry, renewable energy, Li-ion battery

摘要:

采用微波辅助溶剂热法的合成途径,成功制备出镁掺杂的磷酸锰镁锂(LiMn1-xMgxPO4/C)电极材料。采用X-射线衍射、扫描电镜、恒电流充放电等测试方法对晶体结构,微观形态和电化学性能进行表征。结果表明微波辅助溶剂热样品LiMn1-xMgxPO4/C为具备较大比表面积和介孔结构的片层状形貌材料。该片层状纳米结构有利于锂离子脱嵌/镶嵌反应,Mg2+掺杂在片层状纳米晶体合成过程中发挥着重要作用,可以提高材料的电化学活性和电化学表现。其中LiMn0.95Mg0.05PO4/C材料在0.1 C和5 C倍率下最高可逆放电容量分别为141.2和95.3 (mA·h)/g,具备较高的放电容量和倍率性能表现。与传统溶剂热法相比,微波辅助溶剂热法的反应时间显著降低且制备得到的材料具备优异的电化学性能表现,对于制备其他锂离子电池材料具有指导意义。

关键词: 微波合成, 磷酸锰锂, 纳米材料, 电化学, 再生能源, 锂离子电池

CLC Number: