不同酸溶液中恒电压法制备聚苯胺薄膜

Preparation of Polyaniline Film in Different Acid Solutions by Constant Voltage Polymerization

在不同的酸溶液中加入定量苯胺单体,利用电化学恒压法制备了导电性能优良的聚苯胺薄膜,研究了以不同浓度(0.5、1、1.5、2mol/L)的盐酸、高氯酸和对甲苯磺酸为电解质溶液,苯胺在ITO导电玻璃上的聚合电压和颜色变化,并用FT IR、循环伏安和SEM研究了聚合物的结构及性能。研究表明,在不同酸掺杂下薄膜的颜色依次为黄绿色、绿色、深绿色、天蓝色和深蓝色,这是由于不同掺杂酸对阴离子大小的不同导致其分子链上电荷离域不同,从而使得聚合物的掺杂程度不同而发生不同的红移;随着使用电压的增大,溶液中导电能力增强,聚苯胺薄膜的颜色加深;随着同种酸浓度的增加,质子酸的酸性越强,苯胺的聚合电位就越低。

The polyaniline film was prepared through electropolymerization of purified aniline in various acid solutions by the constant voltage method.The potentials of polymerization and the color changes of polyaniline deposited on ITO conductive glass in HCl,HClO4 and CH3C6H4SO3H with different concentration were investigated.The structures and performance of as-prepared polyaniline were characterized by techniques of FT-IR,electrochemical and SEM.It was found that the colors of as-prepared polyaniline thin films were changed from yellow-green and green,green and dark blue,sky blue and dark blue in turn in three doping acids,and the higher voltage and concentration of the acid solutions were,the deeper the color of the film is;in addition,the polymerization potential was decreased as increasing of the acidities of the solutions.Electrochemical performance tests showed that asprepared polyaniline film exhibited good conductivity.