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利用聚乙烯吡咯烷酮(PVP)作为聚合物配位剂和燃料,通过凝胶-燃烧法合成了Li1.07Mn1.93O4纳米片.采用热重/差热分析(TG/DTA)研究了凝胶的燃烧过程.采用X射线多晶衍射(XRD)分析了材料的结构,结果表明合成的Li1.07Mn1.93O4结晶完整,无杂质相.扫描电镜(SEM)结果显示材料的二次形貌为厚度约100nm的片状,由大小约100nm的一次颗粒构成.充放电测试表明Li1.07Mn1.93O4纳米片具备极佳的倍率放电性能和优秀的循环性能.0.5C(1C=120mA.g-1)倍率的初始放电容量为115.4mAh.g-1,即使倍率增大到40C,放电容量仍有105.3mAh.g-1.在10C倍率的放电条件下,循环850次容量保持率为81%.电化学阻抗谱(EIS)测试表明Li1.07Mn1.93O4纳米片的界面电荷转移电阻(Rct)远小于同类商业材料.
Li1.07Mn1.93O4 nanosheets were synthesized by gel-combustion method using polyvinylpyrrolidone (PVP) as polymer complexing agent and fuel.The effects of thermal gravimetric / differential thermal analysis (TG / DTA) The structure of the material was analyzed by X-ray diffraction (XRD). The results show that the synthesized Li1.07Mn1.93O4 crystal is complete and has no impurity phase. The scanning electron microscopy (SEM) results show that the secondary morphology of the material is about 100nm , Which is composed of primary particles with a size of about 100nm.The charge and discharge tests show that the Li1.07Mn1.93O4 nanosheets have excellent rate discharge performance and excellent cycling performance.With 0.5C (1C = 120mA.g-1) The initial discharge capacity of 115.4mAh.g-1, even if the magnification increased to 40C, the discharge capacity is still 105.3mAh.g-1. At 10C rate of discharge conditions, 850 cycles capacity retention was 81%. Electrochemical impedance Spectral (EIS) tests show that the interfacial charge transfer resistance (Rct) of Li1.07Mn1.93O4 nanosheets is much smaller than that of commercial counterparts.