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以Mn Cl_2、KMn O_4和Na OH为反应物原料,采用液相氧化还原法制备得到层状二氧化锰中间体,然后以层状二氧化锰和Na OH为原料,采用水热法制备了OMS-5型(八面体分子筛)纳米Mn O_2电极材料。分别用X射线衍射光谱、扫描电镜和傅里叶-红外光谱等表征样品的晶体结构、形貌和键合特性;采用循环伏安、恒流充放电和交流阻抗等方法研究其电化学性能。结果表明:OMS-5型纳米Mn O_2结晶良好,直径约为50 nm;在0.5 mol/L的Li_2SO_4和Na_2SO_4电解液中,电流密度为0.1 A/g时,其比电容分别为47.4、170.3 F/g;等效串联电阻和漏电流小,在Na_2SO_4电解液中展现出良好的循环稳定性,表明该OMS-5型纳米Mn O_2是一种可能具有应用前景的超级电容器电极材料。
MnCl 2, KMn O 4 and Na OH were used as starting materials to prepare layered manganese dioxide intermediate by liquid phase redox method. Then layered manganese dioxide and Na OH were used as raw materials to prepare OMS -5 (Octahedral Molecular Sieve) Nanometer Mn O 2 Electrode Material. The crystal structure, morphology and bonding properties of the samples were characterized by X-ray diffraction, scanning electron microscopy and Fourier transform infrared spectroscopy, respectively. The electrochemical properties of the samples were investigated by cyclic voltammetry, constant current charge-discharge and AC impedance. The results showed that OMS-5 nano-MnO2 crystallized well and its diameter was about 50 nm. In 0.5 mol / L Li2SO4 and Na2SO4 electrolyte, the specific capacitance was 47.4 and 170.3 F at a current density of 0.1 A / g / g; the equivalent series resistance and leakage current are small, which shows good cycling stability in Na_2SO_4 electrolyte, indicating that the OMS-5 nano-MnO_2 is a potential supercapacitor electrode material.