中文摘要：

由于聚苯胺（PANI）独特的质子酸掺杂机制,其在高pH值溶液中会发生去质子化过程,导致失去导电性和电化学活性,故普通PANI只有在酸性介质中（pH〈4）才具有电化学氧化-还原活性,这成为PANI应用的一大障碍.为解决PANI在高pH值溶液中的＂失活＂问题,人们提出了各种各样的方法.从基于质子酸掺杂机理和基于电荷转移机理的两大解决途径入手,就提高PANI在高pH环境中电化学活性的方法进行了系统综述,重点评述了自掺杂、高分子酸掺杂和碳纳米管掺杂PANI的制备方法、电化学特性以及提高电化学活性的作用机制,并指出了提高PANI高pH环境下的电化学活性所存在的难点及今后的研究方向.

英文摘要：

Generally, the redox activity of polyaniline （PANI） can only be retained in acidic media at pH〈4, because the occurrence of deprotonation of the nitrogen atoms in tho PANI backbone at high pH values may result in the loss of conductivity and electroactivity in neutral or alkaline solutions. This high acidity requirement greatly limits its potential applications like biosensor, marine antifouling and anticorrosion, where neutral or alkaline environments must be faced. Much effort has been exerted in the development of approaches to overcome this issue. In summary, two principal strategies have been pro- posed to shift the electroactivity of PANI to a high pH environment. One is based on a mechanism of protonic acid doping, the other is based on a charge transfer process. The former is to introduce acidic groups into the PANI chains or PANI sys- tems to hinder the deprotonation of its conducting form and thus to preserve its electroactivity at higher pH values. The main approaches to introduction of acidic groups include the sulfonation of the emeraldine base of PANI, the homopolymerization of aniline derivatives with acidic ionogenic groups or the copolymerization of aniline and aniline derivatives, and the formation of PANI complexes by doping with macromolecular acids. The latter is to use a hybrid film fabricated by incorporating conductive nanomaterials into a PANI matrix, which can improve the charge transfer rate across the PANI matrix and facili- tate its redox processes. The development of PANI nanocomposites prepared by doping with carbon nanotubes, graphenes and Au nanoparticles, etc., falls into this category. This review article provides an overview of various approaches to preserve the electroactivity of PANI in high pH solutions on the basis of the two main strategies. Special emphasis is placed on the synthetic methods and electrochemical features for the self-doped, polymer acid-doped and CNT-doped PANIs, including their underlying mechanisms for achieving good electroactivity. The main chall