纳米α-MnO_2的微乳液法制备及其在锌离子电池中的性能  

Electrochemical performance in zinc ion battery of nanosizedα-MnO_2 synthesized by a new microemulsion method

作　　者：杨敬东[1] 张振忠[1] 吴昊天[1] 赵芳霞[1] 裴超[1] 

机构地区：[1]南京工业大学材料科学与工程学院,南京210009

出　　处：《化工新型材料》2015年第8期78-80,共3页New Chemical Materials

基　　金：江苏高校优势学科建设工程项目;广西科技成果转化与推广计划项目(1298009-15)

摘　　要：针对高性能锌离子电池的制备,在AOT/异辛烷反相微乳液体系中,以KMnO4为氧化剂,琥珀酸二(2-乙基己酯)磺酸钠(AOT)同时作为表面活性剂和还原剂制备了纳米α-MnO2。借助X射线衍射(XRD)、透射电子显微镜(TEM)和恒流充放电测试等手段研究了反应温度对粉体晶型和结构形貌及其在模拟锌离子电池中的放电容量和循环性能的影响。结果表明:所制备的粉体为高纯度弱结晶性纳米α-MnO2,且随着反应温度的提高,粉体由无定形态逐渐向三维刺球状颗粒转变,但粉体团聚加重。反应温度为40℃时制备的样品在30mg/cm2高活性物质载量、100mA/g和1000mA/g放电速率下电极比容量分别为212.6mAh/g和98mAh/g,相对于普通低温固相反应法制备的MnO2,放电比容量、高倍率放电性能和循环性能均明显提高。Aiming at the preparation of high performance zinc ion batteries,nanosized α-MnO2 had been synthesized by using AOT/isooctane reverse micelles system,in which reactant KMnO4 was reduced by surfactant sodium bis（2-ethyl- hexyl） sulfosuccinate（AOT）. X ray diffraction（XRD）,transmission electron mieroscope（TEM）,and galvanostatic charge- discharge tests were carried out to investigate the effect of reaction temperature on the morphology and structure of the crystalline powder, discharge capacity and cycle performance of the simulated zinc ion batteries. The results indicated that the as-prepared powders were high purity and poor crystallinity nanosized α-MnO2, with the increase of reaction tempera ture,the amorphous powder products transformed into spherical particles and agglomeration increased greatly. The sample which was obtained with 40℃ had an excellent specific capacitance of 212.6mAh/g and 98mAh/g at the current density of 100mA/g and 1000mA/g and high loading of 30mg/cm2, compared with the α-MnO2 prepared by solid state reaction, the discharge capacity,high rate discharge performance and cycle performance were significantly improved.

关 键 词：自反应微乳液法 纳米α-MnO2 二次锌离子电池 电化学性能 

分 类 号：TM910[电气工程—电力电子与电力传动] O614.711[理学—无机化学]