聚(N-甲基)苯胺电极材料的电化学性质研究

Study on the electrochemical properties of poly (N methyl) aniline electrode materials

为开发综合性能优良的导电聚合物，报道了聚（Ｎ－甲基）苯胺的电化学合成方法；用循环伏安法考察了聚（Ｎ－甲基）苯胺电极反应可逆性；探讨了由聚（Ｎ－甲基）苯胺膜电极、Ｚｎ片、１．０ｍｏｌ／ＬＺｎＣｌ２水溶液（ｐＨ＝２．０１）构成的蓄电池的充放电特性。结果表明：聚（Ｎ－甲基）苯胺作为一种新的蓄电池阴极材料在酸性溶液中有很高的稳定性，膜电极反应是一个准可逆反应。上述电池的开路电压为１．３１Ｖ。在恒电流放电速率为０．１５ｍＡ／ｃｍ２（放电电压为０．９０Ｖ，聚合物质量为２．０ｍｇ／ｃｍ２），聚（Ｎ－甲基）苯胺的比容量、比能量和库仑效率分别为９７．５Ａｈ／ｋｇ，９４．６Ｗｈ／ｋｇ和９５．４％。比容量、比能量和库仑效率值均随放电速率的增加而下降。当聚合物膜电极质量从２．０ｍｇ／ｃｍ２增加至３５．６ｍｇ／ｃｍ２时，在相同的放电速率条件下，电池的比能量值明显下降，这表明嵌入膜内的离子中仅仅是部分离子参与了膜的氧化还原反应，当聚合物膜厚度增加时，内层电活性组分对能量输出无贡献。上述结果对聚苯胺及其衍生物的生产和加工具有积极的意义。

In order to develop the conductive polymers having good comprehensive properties, we reported the electrochemically synthetical method of poly (N methyl) aniline in this papers. The reversibility of the electrode reaction of poly (N methyl) aniline was inspected by cyclic voltammetry. The charge discharge characteristics of the rechargeable batteries which consisted of poly (N methyl) aniline cathode, Zn sheet, and 1.0mol/L ZnCl 2 aqueous solution (pH=2.01) were also explored. The results show that poly (N methyl) aniline, used as a new cathode active material in rechargeable batteries, is very stable in acidic aqueous solution. The electrode reaction of polymer film is a quasi reversible oxidation and reduction reaction. The cell above mentioned had a open circuit voltage of 1.31V. The capacity, energy density and coulombic efficiency of poly (N methyl) aniline were 97.5Ah/kg, 94.6Wh/kg and 95.4%, respectively, at constant discharge current density of 0.15mA/cm 2. When the weight of polymer film electrode was increased from 2.0mg/cm 2 to 35.6mg/cm 2, the energy density apparently falled down at the same discharge rate. This phenomenon indicates that only a part of ions in the film participate in exchange with those of the solution. Therefore, when the thickness of film is increased, the active material in the deep film does not contribute to energy. The above results have active significance for us to produce and process the poly (N methyl) aniline and derivatives in the future.