以三聚氰胺为氮源,通过固相法成功合成了掺氮碳包覆的磷酸铁锂10%-NC-LFP。通过扫描电子显微镜和激光颗粒粒度分析来检测材料的微观形貌和宏观颗粒。颗粒表面氮掺杂的碳层可以提高LiFePO4的电子电导率,与未掺杂的碳(C-LFP)相比,容量更高,倍率性能更好。实验表明,10%-NC-LFP的放电比容量在0.2C时为166mAh/g,在10C时为134mAh/g;C-LFP在0.2C时为164mAh/g,10C时为120mAh/g。本研究方法在提高LiFePO4导电性方面非常有效,可应用于其他正极材料的合成。
The nitrogen-doped carbon-coated lithium iron phosphate (10%-NC-LFP) was successfully synthesized by a simple and effective solid phase method using melamine as a nitrogen source.Microscopic morphology and macroscopic particles of the material were examined by scanning electron microscopy (SEM) and laser particle size analysis.The nitrogen-doped carbon layer on the surface of the particles can increase the electronic conductivity of LiFePO4,and resulted in higher capacity and better rate performance than undoped carbon (C-LFP).The discharge specific capacity of 10%-NC-LFP was 166mAh·g-1 at 0.2C,134mAh·g-1 at 10C,and for C-LFP 164mAh·g-1 at 0.2C,120mAh·g-1 at 10C.The method reported in this paper was very effective in improving the conductivity of LiFePO4 and can be easily applied to the synthesis of other anode materials.
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基金资助
河南工程学院博士基金(D2014020)
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