【摘要】 <正> 关于导电聚吡咯(PP)膜的导电机理,文献上提出的“极化子-双极化子”模型引起了电化学学者的兴趣,该模型认为PP在一定条件下可产生带一个正电荷的极化子(S=1/2)和带两个正电荷的双极化子(S=0)。Scott等人通过ESR研究认为导电PP中担负电荷传输的主要带电物种是双极化子。Genoud等人侧用电化学现场的ESR方法研究PP膜电极在有机溶液中的电化学过程,揭示自旋与电荷载流子之间存在相互关联,认为极化子在导电机理中的作用仍需进一步研究。本文报道PP膜电极在水溶液中的电化学-ESR行为,定性地探讨了电位、电量对PP膜中极化子形成与转化过程的影响,并在PP膜/溶液界面存在电化学反应的情形下,考察了PP膜中可能的电荷传输机理。更多还原

【Abstract】 Electrodes coated with conducting polypyrrole film have been studied in aqueoussolutions by in-situ ESR-electrochemical measurements. It is qualitatively showed thatthe spin concentration is directly dependant on the oxidation state of polypyrrole. It isalso indicated that, in tansient process, the formation of spins and their transformationto spinless structures are correlative with electrochemical oharge injections. Theexperimental results are explained in terms of polaron and bipolaron formations in theelectrochemical redox processes. ESR-electrochemical behaviours of the polymer-coatedelectrodes in solutions containing ascorbic acid have also been investigated. It isbelieved that the charge transfers in polypyrrole film might include contributions fromboth polarons and bipolarons.更多还原