摘要
采用无机盐水溶液反应合成了纳米MnO2粉末。X射线衍射结果表明:所制备的MnO2是αMnO2与γMnO2的混合晶相。透射电 镜分析表明:所制备的MnO2粒径为4~20nm。由所制备的粉末在300℃煅烧3h后作为活性物质制成电极。在1mol/L的(NH4)2SO4电解 液中,在电位范围(以饱和甘汞电极为参比电极)为0.15~0.75V的三电极体系中,通过循环伏安曲线考察了电极的电容性能。循环伏安结果 表明:所制备的纳米MnO2具有优异的电容性能,通过恒流充放电测得其比容量最高可达150.4F/g,循环2~3次后,充放电曲线进入稳定状 态,说明纳米MnO2具有较好的循环充放电性能。作为电极材料,纳米MnO2具有较好的应用前景。
Nano-MnO2 powder was synthesized by inorganic salt water solution reaction of KMnO4 and MnSO4. Results of X-ray diffraction and transmission electron microscope show that the phase of nano MnO2 powder prepared is the mixture of a-MnO2 and γ-MnO2 and its particle size is 4-20 nm. After calcined at 300°C for 3 h, the powder was used as active material to fabricate electrodes. The cyclic voltammograms of electrode prepared by the nano-MnO2 powder show good capacitive performance between 0.15 V and 0.75 V for saturated calomel electrode as reference electrode in 1 mol/L (NH4)2SO4. The maximum capacitance can reach to 150.4 F/g by calculating from the constant current charge/discharge curves. Discharge/charge curves are stabilized after two or three cycles, and the results demonstrate that MnO2 nano-powder has an ideal capacitance property and applications prospect as an electrode material.
出处
《硅酸盐学报》
EI
CAS
CSCD
北大核心
2005年第3期318-322,共5页
Journal of The Chinese Ceramic Society
基金
黑龙江省自然科学基金(B01)资助项目。
关键词
无机盐水溶液反应
二氧化锰
电极材料
超级电容器
比容量
Calcination
Electric discharges
Electrodes
Electrolytes
Manganese compounds
Nanostructured materials
Powder metallurgy
Redox reactions
Salts
Synthesis (chemical)
Transmission electron microscopy
X ray diffraction analysis