加入不同浓度的十二烷基磺酸钠表面活性剂（SDS）改变微乳液溶液介质，用苯胺还原高锰酸钾，制备了不同颗粒大小的纳米片状MnO2材料. 采用X射线粉末衍射、氮吸附比表面测试和扫描电镜及透射电镜表征观察合成材料. 电化学测试表明，0.2 mol•L-1 SDS所合成的纳米MnO2比表面约为228.2 m2•g-1, 在1 mol•L-1 Li2SO4电解液中，该电极比电容达到237 F•g -1（0.1 A•g-1），350 ºC煅烧MnO2电极还可发生可逆Li+嵌脱反应增加其比电容.
Nanostructured MnO2 materials were prepared in a micro-emulsion medium using sodium dodecyl sulfate (SDS）as a surfactant by a redox reaction between potassium permanganate and aniline. The morphologies of the obtained MnO2 were critically dependent on the concentrations of SDS. The particle sizes varied with the change in the micro-emulsion medium. The optimized properties of MnO2 material obtained with the surfactant concentration of 0.2 mol.L-1 had a specific surface area of 228.2 m2.g-1, and delivered a specific capacitance of 237 F.g -1 in 1 mol.L-1 Li2SO4. Additionally, a reversible Li-ion intercalation reaction occurred in the MnO2 calcined at 350 oC.
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