纳米层状二氧化锰的制备及电化学性能研究

以KMnO₄、NaOH和MnCl₂为原料,在室温下采用液相氧化还原法制备了层状二氧化锰电极材料.分别采用X-射线衍射、扫描电子显微镜和N₂吸附-脱附等方法对材料试样的晶型结构、表观形貌和比表面积等物理性能进行了表征; 采用循环伏安、恒流充放电和交流阻抗等电化学方法研究了材料试样的电化学性能.研究结果表明:所制备的层状二氧化锰为纳米材料,比表面积为89 m·g,在0.5 mol·LLi₂SO₄水系电解液中比电容为96.7 F·g,等效串联电阻为1 Ω,漏电流为0.24 mA,800次循环前后具有良好的循环稳定可逆性.

The Preparation and Electrochemical Performances ofanostructured Layered Manganese Dioxide

Nanostructured Layered manganese dioxide as electrode material was prepared by liquid oxidation-reduction method based on KMnO₄,NaOH and MnCl₂as raw materials at room temperature.The physical structures such as the crystal structure,morphology and specific surface area of the as-prepared electrode material were characterized by X-ray diffraction,scanning electron microscopy and nitrogen adsorption-desorption at 77 K,respectively.The electrochemical performances were evaluated by cyclic voltammetry,galvanostatic charge-discharge and electrochemical impedance spectroscopies and so on.The results showed that the obtained material was nanostructured birnessite-type manganese dioxide with BET specific surface area of 89 m·g.The specific capacitance of the Layered manganese dioxide was up to 96.7 F·g in 0.5 mol·L Li₂SO₄ aqueous electrolyteEquivalent series resistance is 1 Ω and leakage current was 0.24 mA,exhibiting excellent cycle and reversible stability in 800 cycles charge-discharge,which maybe have a promising prospect for application in super capacitor.