ZnO修饰对Fe_(1.5)P电化学性能的影响  

Effects of ZnO Modification on the Electrochemical Performance of Fe_(1.5)P

作　　者：李秀丽[1] 王贵欣[1] 闫康平[1] 刘睿[1] 

机构地区：[1]四川大学化学工程学院,成都610065

出　　处：《无机材料学报》2010年第8期877-881,共5页Journal of Inorganic Materials

基　　金：四川大学青年基金(0030705505040)

摘　　要：用流变相法制备了ZnO修饰Fe_(1.5)P电极材料,用X射线衍射仪对产物进行成分分析,用透射电镜表征形貌,用恒流充放电法、循环伏安法和电化学阻抗谱法研究了ZnO修饰对Fe_(1.5)P电化学性能的影响.实验结果表明:ZnO修饰能够提高Fe_(1.5)P的倍率特性,使Fe_(1.5)P的首次放电容量提高～69.7%,达到837.5 mAh/g,经过215次循环后,将Fe_(1.5)P在12C倍率下的放电容量提高～144.3%,而且将Fe_(1.5)P在0.1 C倍率下的恢复放电容量提高～330%;另外,ZnO修饰Fe_(1.5)P的SEI膜阻抗R_(SEI)、电荷传递阻抗R_d和Li^+扩散的Warburg阻抗W_b分别降低～87.9%、～87%和～13.2%,将锂离子扩散系数提高～86.6%.ZnO-modified Fe_（1.5）P powders were synthesized successfully via a rheological phase method.X-ray diffractometry （XRD） was utilized to analyze the composition.TEM was used to characterize the morphology.The effects of ZnO modification on the electrochemical performance of the Fe_（1.5）P were investigated using constant current charge/discharge method,cyclic voltammogram,and electrochemical impedance spectrograph（EIS）.The experimental results show that ZnO modification can enhance the rate performance of Fe_（1.5）P.The first discharge capacity of the ZnO-modified Fe_（1.5）P is 837.5mAh/g,and 69.7%higher than that of the pristine Fe_（1.5）P.After 215 cycles, the discharge capacity of the Fe_（1.5）P at 12C rate is increased to 144.3%.Furthermore,ZnO modification improve 330%of the recovery discharge capability of the Fe_（1.5）P at 0.1 C rate.In addition,in comparison with the pristine Fe_（1.5）P,ZnO modification reduce 87.9%of the SEI film resistance R_（SEI）,87%of the charge transfer resistance R_d,and 13.2%of the Warburg impedance W_b from the diffusion of lithium ions,while can improve 86.6%of the diffusion efficiency of lithium ions.

关 键 词：ZNO Fe_(1.5)P 电化学性能 流变相法 

分 类 号：TM911[电气工程—电力电子与电力传动]