摘要
在不同的反应时间下水热法控制制备发射状超级电容器用MnO2电极材料,采用X射线衍射光谱(XRD)、扫描电镜(SEM)表征其结构,采用循环伏安、恒流充放电和交流阻抗研究其电化学电容性能。结果表明,制备的MnO2为隐钾锰矿型,具有发射状结构,随着反应时间的延长,MnO2的晶型从不完善逐渐变得完善,发射状结构逐渐明显、增大,并且MnO2辐射出的每根单枝从较细的纳米刺逐渐生长为四方结构的纳米棒;在5mA/cm2的电流密度下,最高比电容达到了448F/g;随着反应时间的增加,MnO2电极的比容量先增长再降低。
Emission-like manganese dioxide was controtteu sy - o different reaction time for supercapacitor electrode. The structures were characterized by XRD and SEM, and the supercapacitive behaviors were investigated by cyclic voltammetry （CV）, charge-discharge tests, and ac im- pedance spectroscopy, respectively. The results suggested that the as-prepared manganese dioxides indexed tet- ragonal cryptomelane phase and the morphology of which was emission-like nanoclusters. Crystallinity and structure dimension became larger and the nanostab structure of every single branch was changed into nanorod structure followed with the time. The specific capacitance values of manganese dioxide electrode was 448F/g corresponding to the charge/discharge current densities of 5mA/cm^2. With the prolonging of reaction time, the specific capacitance tended to raise first and then declined.
出处
《功能材料》
EI
CAS
CSCD
北大核心
2013年第19期2882-2887,共6页
Journal of Functional Materials
基金
国家自然科学基金资助项目(51203071
21163010)
教育部科学技术研究重点资助项目(212183)
甘肃省杰出青年基金资助项目(1111RJDA012)
兰州理工大学红柳青年教师基金资助项目(201201)
关键词
超级电容器
水热法
MNO2
电极材料
supercapacitor
hydrothermal method
manganese dioxide
electrode material
