铬掺杂a-MnO_2的制备及其在锌离子电池中的性能  

Preparation of Cr-doping nanosized a-MnO_2 and its electrochemical performance in zinc ion battery

作　　者：肖酉 李振[1] 赵芳霞[1] 史竞成 张振忠[1] XIAO You;LI Zhen;ZHAO Fang-xia;SHI Jing-cheng;ZHANG Zhen-zhong(School of Materials Science and Engineering,Nanjing Tech University,Nanjing Jiangsu 210009,China)

机构地区：[1]南京工业大学材料科学与工程学院,江苏南京210009

出　　处：《电源技术》2018年第10期1504-1506,共3页Chinese Journal of Power Sources

基　　金：江苏高校优势学科建设工程项目(苏政办发2011-6);广西科技成果转化与推广计划项目(1298009-15).

摘　　要：以KMnO_4、MnSO_4·H_2O和K_2Cr_2O_7为原料,采用水热法制备了锌离子电池正极用铬掺杂型纳米a-MnO_2材料。借助XRD、TEM和恒流充放电测试等手段研究了反应时间和Cr掺杂量对MnO_2粉体的晶型结构和形貌及其在模拟锌离子电池中的放电比容量和循环性能的影响。结果表明:所制备的粉体为结晶性良好的纳米棒状a-MnO_2;Cr的掺杂不会明显改变MnO_2的晶体结构,Cr掺杂型纳米a-MnO_2所制备的电池初始放电比容量可达257 mAh/g,与未掺杂的a-MnO_2相比提高了27.9%,10个循环后的容量保持率提高21.8%。推荐性能最佳铬掺杂纳米a-MnO_2的水热法制备工艺参数为:在160℃下,KMnO_4与MnSO_4的摩尔比为2∶3,水热法反应4 h,K_2Cr_2O_7的掺杂量为10%(质量分数)KMnO_4。KMnO4,MnSO4·H2O and K2Cr2O7 were used to obtain chromium doped nanosizedα-MnO2 used in zinc ion battery under the hydrothermal method.XRD,TEM and galvanostatic charge-discharge tests were carried out to investigate the effect of reaction time and Cr doping amount on the morphology and structure of the crystalline powders,discharge capacity and cycle performance of the simulated zinc ion batteries.The results indicate that the as-prepared powders are some nano-rods with good crystallinity.The crystal structure isn’t significantly changed by the Cr doping of theα-MnO2.The initial discharge capacity of the battery prepared by Cr doped nanoα-MnO2 can reach 257 mAh/g,which is 27.9%higher than that of undopedα-MnO2.The capacities retention after 10 cycles increase 21.8%.The process parameters of best performance of Cr-dopingα-MnO2 is proposed for under 160℃,the molar ratio of KMnO4 to MnSO4 is 2∶3 and 4 h with 10%KMnO4 of K2Cr2O7 by hydrothermal preparation.

关 键 词：纳米α-MnO2 铬掺杂 水热法 锌离子电池 电化学性能 

分 类 号：TM912[电气工程—电力电子与电力传动]