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采用水热法结合短时间高温烧结,通过将前驱体pH值从3.00调节到9.00,制备出多种形貌的纯相LiFePO4。对所得产物进行了X射线粉末衍射(XRD)测试、扫描电子显微镜(SEM)表征以及电化学性能测试,研究了前驱体pH值对LiFePO4的形貌和电化学性能的影响及其机理。结果表明,产物均为橄榄石型LiFePO4,并显示出由棒状物组成的空心球形、凹陷形以及菱形和多层菱形等多种形貌。不同形貌LiFePO4的电化学性能差异较大,当前驱体pH=6.00时电化学性能最佳,在0.1C和5C下首次放电比容量分别为163mAh.g-1和100mAh.g-1。
Abstract：The pure phase of the LiFePO4 with several interesting crystal morphologies was prepared by hydrothermal method with the precursor pH values varying from 3.00 to 9.00 followed by short-time sintering.The characterizations of the products were performed by powder X-ray diffraction(XRD),scanning electron microscopy(SEM) and electrochemical test,and the mechanism and influences of the precursor pH value on the morphology and electrochemical pro-perties of LiFePO4 were investigated.The results show that the LiFePO4 samples crystallize well in an olivine-type structure,and display hollow microsphere and concave morphologies made up by rods,as well as rhombic and multilayer rhombic morphologies.LiFePO4 samples with diffe-rent morphologies exhibit quite different electrochemical properties.The excellent electrochemicalproperties of the sample were obtained at the precursor pH value of 6.00.And the sample delivers initial discharge capacities of 163 mAh·g-1 and 100 mAh·g-1 at 0.1 C and 5 C,respectively.
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基本信息:
中图分类号:TF124.5
引用信息:
[1]李传玲,康雪雅,吐尔迪,等.前驱体pH值对LiFePO_4形貌和电化学性能的影响[J].微纳电子技术,2011,48(08):499-503+527.
基金信息:
中国科学院“西部之光”人才培养计划资助项目(XBBS200919);; 新疆维吾尔族自治区科技厅高技术研究发展计划资助项目(200716117)
2011-08-15
2011-08-15