论文部分内容阅读
在0.5 mol·L-1H2SO4水溶液中,以ITO导电玻璃为工作电极,用原位紫外-可见光谱进行跟踪恒电位电聚合间甲基苯胺和邻甲基苯胺.结果表明邻甲基苯胺的电化学聚合要比间甲基苯胺快.在0.9 V(vs.饱和Ag/AgCl)恒电位电解时的电流-时间响应曲线表明聚间甲基苯胺和聚邻甲基苯胺在导电玻璃上的沉积方式是不同的,在电解初期两者均可能以时间累积成核方式沉积,但随着电解的进行,邻甲基苯胺电化学聚合发生支链化,而间甲基苯胺的电化学聚合反应却变慢.扫描电镜图表明聚邻甲基苯胺具有多孔颗粒状的表面形貌,而聚间甲基苯胺却具有致密的表面形貌.量子化学从头计算(6-31**/B3LYP)表明,半氧化态的间甲基苯胺四聚体发生了明显的卷曲而与此对应的邻甲基苯胺四聚体却没有明显的卷曲;这说明尽管聚邻甲基苯胺和聚间甲基苯胺在化学结构上是类似的,但它们的空间结构可能存在明显的不同,导致其聚合和在电极沉积的方式可能产生较大的差别.
In 0.5 mol·L-1 H2SO4 aqueous solution, ITO conductive glass was used as working electrode, and the in-situ UV-Vis spectra were used to trace the potentiostatic polymerization of methylaniline and o-methylaniline. The results showed that the electro- The polymerization was faster than m-methylaniline.The current-time response at 0.9 V (vs. Saturated Ag / AgCl) potentiostatic electrolysis indicated that the deposition of poly (m-methylaniline) and poly (o-methylaniline) on the conductive glass was In contrast, both of them may accumulate in a time-dependent manner during the initial electrolysis, but as the electrolysis progresses, the electrochemical polymerization of o-methylaniline branches and the electrochemical polymerization of m-methylaniline slows down Scanning electron micrographs show that poly-o-methylaniline has a porous and granular surface morphology, while poly-m-methylaniline has a dense surface morphology. Quantum chemical ab initio calculations (6-31 ** / B3LYP) State of the m-methylaniline tetramer obvious crimp and the corresponding o-methylaniline tetramer no significant curl; This shows that although poly-o-methyl aniline and poly-m-methylaniline in the chemical structure Are similar, but their spatial structure may exist In obvious contrast, there may be a large difference in the way they aggregate and deposit on the electrode.