Abstract In this work, undoped and doped polyaniline (PANI) films with benzoic acid were fabricated using N-methyl-2-pyrrolidone (NMP) as the solvent. Doped PANI films were prepared from 0 to 25 wt.% contents of benzoic acid. Spectroscopic and electrical measurements were made to elucidate the doping effect caused by benzoic acid. Films doped up to 15 wt.% showed an enhanced increase in electrical conductivity, attributed to the combined effects of protonation and counter ion interaction with the polymer chains. Films with superior benzoic acid contents (e.g., 20 and 25 wt.% of benzoic acid) showed a continued increase in the conductivity. The results also revealed that there is an excess of counter ions in these films responsible for making the inter-chains conductivity more difficult. The evolution of the conductivity with the doping degree was discussed using an equivalent circuit model.

中文翻译：

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苯甲酸掺杂聚苯胺薄膜中的电荷传输

摘要 在这项工作中，使用 N-甲基-2-吡咯烷酮 (NMP) 作为溶剂制备了含有苯甲酸的未掺杂和掺杂的聚苯胺 (PANI) 薄膜。从 0 到 25 wt.% 的苯甲酸含量制备掺杂的 PANI 薄膜。进行光谱和电学测量以阐明苯甲酸引起的掺杂效应。由于质子化和反离子与聚合物链相互作用的综合效应，掺杂至 15 wt.% 的薄膜显示出电导率的增强。具有较高苯甲酸含量（例如，20 和 25 重量% 的苯甲酸）的薄膜显示出电导率的持续增加。结果还表明，这些薄膜中存在过量的反离子，导致链间导电性更加困难。