不同状态下聚吡咯膜的电化学阻抗

Electrochemical Impedance of Polypyrrole Films under Different Conditions

用恒电流法分别聚合了掺杂对甲苯磺酸根(pTS-)和十二烷基磺酸根(DS-)的聚吡咯膜(PPy/pTS和PPy/DS),通过循环伏安法(CV)和电化学阻抗法(EIS)测试了聚吡咯膜在NaCl溶液中‘过电位’电化学过程前后及不同电位下聚吡咯膜的电化学性能.同时,通过嵌入和脱出Na+和Cl-离子的聚吡咯膜在特定溶液中电化学阻抗图谱,研究了离子的嵌入对聚吡咯膜电化学性能的影响.结果表明‘过电位’现象可以提高聚吡咯膜的离子电导率和膜电容,Cl-离子的嵌入能提高PPy/pTS的电导率,而Na+离子的嵌入对聚吡咯膜的电导率影响不大.另外,嵌入离子对聚吡咯膜形貌的改变会对聚吡咯膜的离子传导率有一定影响,从而导致膜的电化学阻抗的变化.

We electropolymerized polypyrrole （PPy） films doped with para-toluene sulfonate （pTS-） and dodecyl sulfonate （DS-） by a galvanostatic method.The influence of potential and overpotential process on the electrochemical properties of the PPy films in NaCl aqueous solution were investigated by cyclic voltammetry （CV） and electrochemical impedance spectroscopy （EIS）.In addition,the influence of insertion with or without ions on the PPy films was also studied by the EIS of PPy inserted with or without Na＋ or Cl^-ions in specially prepared aqueous solutions.Results showed that the ionic conductivity and the capacitance of the PPy films increased after the first CV and the electronic conductivity of the PPy/pTS increased after the insertion of Cl^-ions.However,PPy films inserted with or without Na＋ ion showed little difference in the EIS of the PPy films.Furthermore,the ion conductivity was affected by a change in the microstructure of the PPy films with or without ions which was also apparent in the EIS.