新型核壳结构Fe_3O_4/H_xMn_yO_4纳米粒子的制备

Preparation of novel core-shell structured Fe_3O_4/H_xMn_yO_4 nanoparticles

采用自制的多通道撞击流反应器合成以纳米Fe3O4为内核,表面均匀包覆碳酸锰的核壳结构载体.用沉淀法在载体上包覆碳酸锂,再浸渍上一定量硝酸锂,形成"三明治"结构的锂离子筛前躯体,焙烧、脱锂后得到新型核壳结构的锂离子筛Fe3O4/HxMnyO4.实验中制备四种锂离子筛前躯体:Fe3O4/MnCO3/Li2CO3,Fe3O4/MnCO3/LiOH,Fe3O4/MnCO3/LiNO3,Fe3O4/MnCO3/Li2CO3/LiNO3,以及Li2CO3与LiNO3不同比例的Fe3O4/MnCO3/Li2CO3/LiNO3,并对不同组合下得到的锂离子筛性能,包括Fe,Mn的溶损率和对Li脱附率进行表征、分析,得出包覆Li2CO3/0.65LiNO3制得的新型锂离子筛性能最好.

Abstract： The newly-designed multi-channel impinging stream reactor was first employed to synthesize nano Fe304/MnCO3 carrier. Subsequently, lithium carbonate and lithium nitrate were precipitated on the carrier to obtain sandwich-structured lithium ion sieve precursor, which was calcined to obtain Fe304/LixMnyO4 nanopowders. After this, cation resins were employed to release Li＋ ions from Fe304/LixMny04 suspension to obtain Fe304/HxMnyO4 powders. Furthermore, four kinds of lithium ion sieve precursor including： Fe304/MnCO3/Li2C（）：~, Fe3 04/MnCO3/LiOH, Fe3 04/MnCO3/LiNO3 and Fe3 04/MnCO3/Li2 CO3/LiNO3 were prepared, calcined and investigated their properties to search the optimum precursor. The results indicated that the precursor of Fe3O4/MnCO3/Li2CO3/LiNO3 in which the molar ratio of Li2CO3/LiNO3reached to 0.65 was the best.