摘要
以磷铁废渣(Fe1.5P)和温室效应气体CO_2为原料,以磷酸为补充磷源合成磷酸铁锂(LiFePO_4)的前驱体Fe_2P_2O_7,并研究了其合成过程对LiFePO_4正极材料储能性能的影响。采用SEM观察了LiFePO_4的表面形貌,采用XRD分析了LiFePO_4和Fe_2P_2O_7的晶体结构。进一步对该方法进行优化,发现Fe1.5P与磷酸混合物(nFe1.5P∶nH3PO4=1∶1)在800℃热处理6 h合成的Fe_2P_2O_7对应的LiFePO_4/C电化学性能最好,在0.1C,0.2C,0.5C和1C倍率下的容量分别可达130,126,117和108 m Ah·g^(-1)。
Fe2P2O7 was prepared from Fe-P waste slag and CO2 using a solid-state method, and it was furtherly used as precursor of LiFePO4. The compositions and microstructures of the as-synthesized Fe2P2O7 and LiFePO4 were characterized by TG/DSC, XRD and SEM. It is found that Fe1.5P can be oxidized to Fe2P2O7 over 700℃ in CO2 atmosphere. The optimized synthesis of Fe2P2O7 is described as：mixture of Fe1.5P and H3PO4 （extra P source） is calcined at 800℃ for 6 h, which gives the highest specific capacity of LiFePO4. The discharge capacity of the as-synthesized LiFePO4 can reach as high as 130, 126, 117, and 108 mAh·g-1 with C-rates of 0.1C, 0.2C, 0.5C and 1C, respectively.
出处
《无机化学学报》
SCIE
CAS
CSCD
北大核心
2018年第2期263-269,共7页
Chinese Journal of Inorganic Chemistry
基金
financially supported by the National Science Foundation of China (Grant No.21576170)
the Opening Project of Material Corrosion and Protection Key Laboratory of Sichuan province (Grant No.2017CL19)~~
