烧结温度对Fe(OH)3胶体制备Fe2O3材料储锂性能的影响  

Effect of calcination temperature on lithium storage performance of FeO material prepared from Fe(OH)colloid

作　　者：姚金环 张竹柳[1,2] 杨永德 李延伟 YAO Jinhuan;ZHANG Zhuliu;YANG Yongde;LI Yanwei(Guangxi Key Laboratory of Electrochemical and Magnetochemical Functional Materials,Guilin 541004,Guangxi,China;College of Chemistry and Bioengineering,Guilin University of Technology,Guilin 541004,Guangxi,China)

机构地区：[1]广西电磁化学功能物质重点实验室,广西桂林541004 [2]桂林理工大学化学与生物工程学院,广西桂林541004

出　　处：《精细化工》2020年第8期1621-1628,共8页Fine Chemicals

基　　金：国家自然科学基金(51964012);广西自然科学基金(2017GXNSFAA198117)。

摘　　要：以Fe(OH)3胶体为铁源,探索了一步烧结法制备二维片状结构Fe2O3电极材料,考察了烧结温度(400、500、600和700℃)对材料微观结构和储锂性能的影响。结果表明:400℃烧结的样品为α-Fe2O3/Fe3O4复合材料,其他温度烧结得到的是纯的α-Fe2O3;随着烧结温度的升高,组成片状结构致密相连的不规则颗粒逐渐分离,二维片状结构接近坍塌。电化学性能研究发现:500℃下得到的样品电极具有相对较好的储锂性能,在1 A/g的电流密度下循环450圈后放电比容量达628.6 mA·h/g,当电流密度为4 A/g时,放电比容量仍有352.3 mA·h/g。动力学及电极稳定性分析发现,500℃烧结的样品Li+扩散系数最大(还原峰和氧化峰对应的扩散系数值分别为:1.57×10^-13和4.60×10^-13 cm2/s),充放电循环过程中结构稳定性最好。Two-dimensional flake Fe2O3 electrode materials were prepared by one-step sintering method using Fe(OH)3 colloid as iron source.The effects of sintering temperature(400,500,600,and 700℃)on the microstructure and lithium storage performance of Fe2O3 samples were investigated.The results demonstrated that the sample sintered at 400℃wasα-Fe2O3/Fe3O4 composites,while the samples sintered at 500,600,and 700℃were single phaseα-Fe2O3.With the increase of sintering temperature,the tight connected irregular particles in the flake gradually got separated so that the two-dimensional flake structure tended to collapse.The results of electrochemical performance tests showed that the electrode prepared from the sample sintered at 500℃exhibited relative good lithium storage performance,a high specific discharge capacity of 628.6 m A·h/g still remained after 450 cycles at 1 A/g,and the specific discharge capacity maintained at 352.3 m A·h/g even at 4 A/g.The kinetic and the cycling stability results revealed that this electrode had the largest Li+diffusion coefficient(the diffusion coefficient values corresponding to reduction peak and oxidation peak are 1.57×10^-13 and 4.60×10^-13 cm2/s,respectively),and displayed the best structural stability in the process of charging and discharging cycle.

关 键 词：氧化铁 负极材料 锂离子电池 氢氧化铁胶体 蔗糖 有机电化学 

分 类 号：TM192[电气工程—电工理论与新技术]