摘要
以离子液体1-丁基-3甲基咪唑二腈胺盐为碳源,通过微波辅助加热法制备LiFePO_4/C正极材料。采用X射线衍射(XRD)表征了样品的物相,扫描电镜(SEM),透射电镜(TEM)考察了样品的微观形貌,元素分析检测了离子液体最终产物中C、H、N元素的含量。通过恒电流充放电测试研究了材料的电化学性能,主要研究了加热方式和Mg2+掺杂对材料性能的影响。结果表明,微波加热可以高效快速制备LiFePO_4/C,有利于离子液体碳化形成碳层。在加热时间较长的情况下,会造成颗粒的不规则长大。Mg2+的掺杂不会改变LiFePO_4/C颗粒的形貌,0.1C倍率下首次放电比容量达到146.3mAh/g,经过45次循环后容量没有明显衰减,可以有效地改善LiFePO_4/C的电化学性能。
Using ionic liquid 1-butyl-3methylimidazolium dicyanamide（[BMim][N（CN）2]）as carbon sources,the LiFePO_4/C anode materials were synthesized by microwave assisted heating method.The samples were characterized by Xray diffraction,SEM and TEM.Elemental analysis was made to detect the content of each element of final product of ionic liquid.The galvanostatic charge-discharge test was used to investigate the electrochemical properties of samples.The influence of heating method and Mg2＋doping were mainly studied.These results indicated that LiFePO_4/C could be efficiently and rapidly prepared by microwave assisted heating method.Microwave was beneficial to the carbon layer formed by carbonization of ionic liquid.Irregular growth of the LiFePO_4/C particles could be occurred under the condition of longer heating time.Mg2＋doping could not change the morphology of LiFePO_4/C.LiFePO_4/C doped with Mg2＋had an initial discharge specific capacity of 146.3mAh/g at 0.1C.Furthermore,the discharge specific capacities of the LiFePO_4/C did not fade out after 45 cycles.
出处
《化工新型材料》
CAS
CSCD
北大核心
2016年第3期56-58,共3页
New Chemical Materials
基金
国家自然科学基金项目(51364024
51404124)
