【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。更多还原

【Abstract】 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 αMnO₂ and γMnO₂ and its particle size is 4—20 nm. After calcined at （300 ℃） 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.更多还原