乙醇-水体系3D纳/微米球形磷酸铁的制备与表征  

Synthesis and characterization of 3D nano/micro spherical iron phosphate in ethanol-water system

作　　者：吴康 李军[1] 陈明 Wu Kang;Li Jun;Chen Ming(School of Chemical Engineering,Sichuan University,Chengdu 610065,China)

机构地区：[1]四川大学化学工程学院,四川成都610065

出　　处：《无机盐工业》2020年第6期41-45,共5页Inorganic Chemicals Industry

摘　　要：提出了一种在温和条件下制备高振实密度球形磷酸铁的简单方法。制备过程中无需引入碱性物质调节p H和添加其他模板剂,仅以九水合硝酸铁[Fe(NO3)·9H2O]和磷酸(H3PO4)为原料,在乙醇-水体系中即可制备3D纳/微米球形磷酸铁(记为FPE)。采用扫描电镜(SEM)、激光粒度仪、X射线衍射仪(XRD)、热重-差式扫描量热仪(TG-DSC)、比表面积测试仪(BET)等对制备的磷酸铁进行表征分析。结果显示,制备的磷酸铁具有3D纳/微米球形结构,平均一次粒径为27.2 nm,二次粒径D50为3.75μm。FPE的组成为二水合磷酸铁(FePO4·2H2O),纯度较高,具有介孔结构,平均孔径为2.75 nm,比表面积为22.41 cm2/g,同时具有较高的振实密度(1.34 g/cm3)。3D纳/微米球形磷酸铁制备方法简单,性能优异,以其为前驱体制备的磷酸铁锂(LiFePO4/C)具有较高的振实密度(1.46 g/cm3),在0.2C倍率下的放电比容量为157.9 mA·h/g。A simple method for preparing high tap density spherical iron phosphate under mild conditions was proposed.Iron phosphate with 3D nano/micro spherical structure(FPE)was prepared by using ferric nitrate[Fe(NO3)·9H2O]and phosphoric acid(H3PO4)as raw materials in a mixed solution of ethanol and water without introducing alkaline substances for p H adjusting and other templating agents.The obtained products were characterized by SEM,laser particle size analyzer,XRD,TG-DSC and BET.The results indicated that the iron phosphate prepared by this method had a 3D nano/micro spherical structure,an average primary particle diameter of 27 nm and a secondary particle diameter D50of 3.75μm.The composition of FPE was iron phosphate dihydrate Fe PO4·2H2O with high purity.The FPE had a mesoporous structure with average pore diameter of 2.75 nm,specific surface area of 22.41 cm2/g and high tap density of 1.34 g/cm3,3D nano/micro spherical iron phosphate is simple to prepare and has excellent performance.The lithium iron phosphate Li Fe PO4/C prepared by using the precursor FPE has a high tap density of 1.46 g/cm3,and the discharge capacity is 157.9 m A·h/g at 0.2C.

关 键 词：乙醇-水体系 球形磷酸铁 纳/微米结构 

分 类 号：TQ126.35[化学工程—无机化工]