电沉积法制备超级电容器电极材料纳米MnO_2

The Preparation of Nanostructure MnO_2 for Supercapacitor Electrode Material by Electrodeposition

采用恒电流、恒电位及循环伏安三种电沉积方法在石墨上从pH为5.7,浓度为0.16 mol/L MnSO4水溶液中分别制备了具有纳米结构的超级电容器活性电极材料MnO2.用扫描电镜测试了其结晶形貌,用电化学研究了其在不同浓度的Na2SO4溶液中的电容特性,计算了它们的比电容,并对测试结果进行了比较和分析.结果表明:MnO2的形貌及性能与沉积方法有关,所合成的MnO2的粒径大约50 nm;用恒电流沉积法制备的样品,在0.3 mol/L的Na2SO4溶液中比电容最高,可达306.75 F/g.

Manganese dioxide deposits with nanostructures （ MnO2 ） were electrochemically deposited on- to graphite substrate from 0. 16 mol/L MnSO4· 5H2O with pH 5. 7 by means of the potentiostatic, gal- vanostatic and cyclic vohammetry techniques. Properties of MnO2 were characterized by SEM technique and cyclic voltammetry. Results showed the structure of MnO2 depend strongly on the deposition mode, the even size of particle is about 50 nm by electrochemically deposited, the results of cyclic voltammetry in Na2SO4 electrolyte indicate that the maximum specific capacity of the material deposited by galvanostatic technique is 306.75 F/g in 0. 3 mol/L Na2SO4.