ZnFe2O4的固相法和水热法制备及其电化学性能研究

摘要

Spinel structure ZnFe2O4 were prepared by solid state reaction and hydrothermal method.Investigations on X-ray diffraction ( XRD), scanning electron microscopy (SEM) and specific area measuements indicate that the samples are well-crystallized cubic spinel structre with average particle sizes of 500 nm and 200 nm and specific areas of 136.7 m2g -1and 382.5 m2g-1 for solid state reaction and hydrothermal method, respectively.The ZnFe2O4 samples show high lithiumstorage capacity and good reversibility.Compared with the sample prepared by solid state reaction, ZnFe2O4 prepared by hydrothermal method demonstrate better electrochemical performances.Its specific charge capacity decays from 750 mAh g-1 to 702 mAh g-1 after 30 cycles, with capacity retention of 93.6 ％.ZnFe2O4 is a very promising anode material for lithium ion battery for its easy preparation, low coat and good electrochemical performances.%本文用固相反应法和水热法制备了ZnFe2O4材料,X射线衍射(X-ray diffraction,XRD)表明制备出来的ZnFe2O4为尖晶石结构,表面形貌测试(scanning electron microscopy,SEM)显示两种方法制备的材料的平均粒径分别为500 nm和200nm.比表面积测试结果表明,两种方法制备的样品的比表面积分别为136.7 m2g-1和382.5 m2g-1.充放电测试结果显示,所制备的ZnFe2O4有较高的储锂容量和良好的可逆性;且用水热法制得的ZnFe2O4材料比用固相法制得的样品具有更加优良的电化学性能:经过三十周的循环,其充电容量从750 mAh g-1衰减到702 mAhg-1,容量保持率为93.6%.ZnFe204材料的制备方法简单,成本低,可逆容量大,有希望作为一种新型锂离子电池的负极材料.