Schiff碱基过渡金属镍络合物的电化学聚合：阳极电聚合中扫描速率的影响(英文)

Electropolymerization of Nickel Complexes with Schiff Bases:Effect of Sweep Rate on Anodic Polymerization

采用线性电位扫描法制备了水杨醛-Schiff碱基过渡金属镍络合物的聚合物poly[Ni(salen)],扫描速率为5-150 mV.s-1.采用场发射显微镜观察了聚合物poly[Ni(salen)]的表面形貌.研究了电聚合中扫描速率对聚合物生长的影响,电聚合速率(dГ/dm)与扫描速率(v)呈指数衰退关系,通过库仑电量分析指出电聚合扫描速率在20mV.s-1时聚合产物中含有最多的氧化还原活性点.扫描速率提高时单体的扩散步骤限制了聚合物的生长,所以氧化还原活性点总量随着扫描速率的提高而开始下降.利用循环伏安法分析了聚合物poly[Ni(salen)]的扩散动力学,结果表明在20 mV.s-1时制备的聚合物具有较大的电荷扩散系数.

Anodic electrochemical polymerization of N,N′-ethylenbis（salicylideneaminato） nickel（II）（[Ni（salen）]） in tetrabutylammonium perchlorate（TBAP）/acetonitrile（AN） was investigated by the linear sweep potential method.The sweep rate ranged from 5 to 150 mV.s-1.The effect of sweep rate on the growth of poly[Ni（salen）] was studied by Coulomb analysis.The morphologies of poly[Ni（salen）] were characterized by field emission scanning electron microscopy（FESEM）.The relationship between the growth rate of poly[Ni（salen）]（dГ/dm） and the sweep rate（v） fits the exponential degradation equation.The content of the redox center for poly[Ni（salen）],grown at sweep rate of 20 mV.s-1,reaches a maximum and then decreases as the sweep rate increases because monomer diffusion restricts the growth of poly[Ni（salen）].We studied the effect of polymerization sweep rate on the kinetics of the as-grown poly[Ni（salen）] by cyclic voltammetry.The charge diffusion coefficient（D） of poly[Ni（salen）] grown at a sweep rate of 20 mV.s-1 was found to be the highest.