锰/炭混合超级电容器阳极材料的制备及性能

采用高锰酸钾与乙酸锰溶液通过液相沉淀法制备了颗粒尺寸为100 nm左右的α-MnO_2,并以此α-MnO_2为锰/炭混合超级电容器阳极材料,采用循环伏安法研究了其在0.5 mol/L Na_2SO_4、1 mol/L KOH溶液、1 mol/L KCI溶液和2mol/L(NH_4)_2SO_4溶液中的充放电行为.结果表明:在0.5 mol/L Na_2SO_4溶液中表现出较好的电容行为,比电容为145F/g.为提高所制备α-MnO_2的比表面积和电导率,将适量具有规则结构的介孔炭(OMC)添加到α-MnO_2中,制备得到MnO_2/OMC复合阳极材料.详细研究了OMC添加量对复合阳极材料结构和性能的影响.掺炭量为20%(质量分数)的锰炭复合物阳极材料的比电容值高达182 F/g.

Synthesis and electrochemical performance of anode materials for MnO_2/C hybrid supercapacitor

α-Manganese dioxide with surface area of 147 m~2/g was synthesized by liquid-decomposition method using potassium permanganate(KMnO_4)and manganese acetateMn(Ac)_2]as reactants.The electrochemical performance of as-synthesized α -MnO_2 was tested by cyclicvoltammetry method in 1 mol/L KOH,1 mol/L KCl,2 mol/L (NH_4)_2SO,and 0.5 mol/L Na_2SO_4 solution,respectively.The results show that α-MnO_2 exhibites nearly ideal specitic capacitance behavior in 0.5 mol/L Na_2O_4 solution and the determined specitic capacitance is 145 F/g.In order to further improve the specific surface area and conductivity of α-MnO_2,certain amount of ordered mesoporous carbon (OMC)was added to form MnO_2/OMC composite.The influence of amount of OMC on the capacitance of MnO_2/OMC anode was investigated.When 20% of OMC is added,the MnO_2/OMC anode materials exhibite the optimal electrochemical behavior and the specitic capacitance reache to 182 F/g.