pH-controlled morphological structure of polyaniline during electrochemical deposition
pH-controlled morphological structure of polyaniline during electrochemical deposition
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DOI：
10.1016/j.electacta.2009.05.075
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发表时间：
2009-11
影响因子：
6.6
通讯作者：
Xu-Yuan Peng;F. Luan;Xiao-Xia Liu;D. Diamond;K. Lau
中科院分区：
文献类型：
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作者：
Xu-Yuan Peng;F. Luan;Xiao-Xia Liu;D. Diamond;K. Lau
聚苯胺（PAni）的电沉积在从pH 0.0至14.0的宽pH范围内进行。发现PAni膜以快得多的速率从强酸性环境中生长，并且似乎采用与从较高pH介质中生长的那些不同的生长模式，从而产生具有非常不同的形态的PAni膜，从纳米纤维到微米级小管到薄片状结构。PAni膜的各种形态是电化学聚合过程中均相成核和异相成核的结果。这些现象发生在特定的条件下，可以通过改变反应介质的pH值来诱导。从增加的pH环境中沉积的膜的特征IR光谱表明除了从pH 14.0生长的膜之外，聚合物的化学结构几乎没有差异。循环伏安法数据也表明不同的电子转移效率作为一个结果，采用不同的形态。在0.5M H2SO4和1.0M NaNO3（pH 1.0）溶液中，使用1.0mAcm− 2的充放电电流密度，除了在pH 2.0至4.0范围内获得的PAni膜外，所有膜都具有约450Fg− 1的高比电容。
Electrodeposition of polyaniline (PAni) was performed across a broad pH range from pH 0.0 to 14.0. PAni films were found to grow from strong acidic environments at much faster rate and appeared to adopt different growth patterns from those grown from higher pH media, thus producing PAni films with very different morphologies ranging from nanofibres to microsized tubules to flakes like structures. The various morphologies of the PAni films were results of homogeneous and heterogeneous nucleation during electrochemical polymerization. These phenomena occurred under specific conditions which could be induced by varying the pH of the reaction media. Characteristic IR absorptions of the films deposited from increasing pH environment indicated little differences in chemical structure of the polymers except for the film grown from pH 14.0. Cyclic voltammetry data also indicated different electron transfer efficiency as a result of different morphology adopted. All except for PAni films obtained from pH 2.0 to 4.0 gave high specific capacitance at around 450Fg−1in 0.5M H2SO4and in 1.0M NaNO3(pH 1.0) solution using 1.0mAcm−2charging and discharging current density.