摘要
以LiOH,(NH_(4))_(2)Fe(SO_(4))_(2)和NH_(4)H_(2)PO_(4)为原料,抗坏血酸为添加剂通过水热法制备出了{010}晶面择优生长的LiFePO_(4)纳米片,在此基础上以MnSO_(4)为锰源,制备了锰掺杂磷酸铁锂复合材料LiFe_(1-x)Mn_(x)PO_(4)/C(x=3%、5%、7%),并研究了不同Mn^(2+)掺杂量对LiFePO_(4)的晶体结构和充放电、交流阻抗(EIS)等电化学性能的影响.XRD、SEM和EDS测试结果表明:Mn^(2+)成功掺入到了LiFePO_(4)晶格中,掺杂后的材料仍是具有橄榄石结构的纳米片,且具有更小的颗粒尺寸,但是{010}晶面的择优情况在一定程度上被抑制了.恒流充放电测试中,在0.1 C倍率下,材料Li Fe_(0.95)Mn_(0.05)PO_(4)/C的首次放电比容量达到了165.26 m A·h g^(-1),表现出了良好的电化学性能.交流阻抗测试结果表明Mn^(2+)的掺杂降低了电荷迁移电阻,提高了材料的电子导电率.
LiFe1-xMnxPO_(4)(x=0%,3%,5%,7%)was prepared by hydrothermal method.M icrostructure and electrochemical properties of the were studied.The structure and morphology of the samples were characterized by X-ray diffraction(XRD)and scanning electron microscope(SEM),electrochemical performances were investigated by constant current charge-discharge and electrochemical impedance spectroscopy(EIS).The results showed that Mn-doped LiFePO_(4)preserved pure olivine structure and nanoplates morphology.Although the preferred growth of{010}planes was inhibited in some degree,but the particle size decreased and the electronic conductivity of LiFe_(1-x)Mn_(x)PO_(4)increased.The Mn-doped LiFePO_(4)had a reversible capacity of 165.26 mA.h g^(-1)at 0.1 C discharge rate,and showed good electrochemical properties.
作者
陈路路
杨柳
刘双任
陈金伟
王瑞林
CHEN Lu-lu;YANG Liu;LIU Shuang-ren;CHEN Jin-wei;WANG Rui-lin(School of Materials Science and Engineering,Sichuan University,Chengdu 610065,P.R.C.)
出处
《西南民族大学学报(自然科学版)》
CAS
2015年第3期373-378,共6页
Journal of Southwest Minzu University(Natural Science Edition)
基金
四川省应用基础研究(2013JY0150)
中物院科研基金(HG2012039)
四川省科技支撑计划(2013FZ0034)
