亚胺基团对Schiff碱基过渡金属聚合物电化学性能的影响

Effects of imino groups on the electrochemical properties of transition metal complexes polymer with Schiff base

采用化学合成法分别制备具有不同亚胺基团的单体Ni(salen)、Ni(salphen),并分别配制成浓度为1 mmol/L单体溶液.在电化学工作站上,以制备好的碳纳米管电极片为工作电极,用循环伏安法进行电化学聚合得到对应的Schiff碱基过渡金属聚合物.用场发射扫描电镜观察聚合物的微观形貌,以及进行循环伏安法、恒流充放电法、交流阻抗谱测试.结果显示,聚合物poly[Ni(salen)]在碳纳米管层表面形成了带状聚合物,而聚合物poly[Ni(salphen)]沿着碳纳米管沉积生长.经测试得知:聚合物poly[Ni(salen)]和poly[Ni(salphen)]的最大电荷扩散系数分别为1.86×10^(-9)cm^2/s、1.23×10^(-8)cm^2/s,并且在0.05 m A/cm^2下的比容量分别为66.6 F/g、106.3 F/g.具有亚胺苯环基团的Schiff碱基过渡金属聚合物电化学性能较具有亚胺乙基基团的电化学性能更好.

Schiff base monomer Ni（salen）and Ni（salphen）with different imino groups were chemical synthetized and formulated as a solution with the concentration of 1 mmol/L.Poly[Ni（salen）] and poly[Ni（salphen）]were electrodeposited on the prepared MWCNTs electrode through cyclic voltammetry on electrochemical workstation.Surface morphologies of poly [Ni（salen）] and poly [Ni（salphen）] electrodes were characterized by field emission scanning electron microscopy（FESEM）and electrochemical properties were test by cyclic voltammetry,chronoamperometry,galvanostatic charge/discharge methods.The results show that poly[Ni（salen）]nano-belts are electrodeposited upon MWCNTs,and the poly[Ni（salphen）] are adhesively grown on nanotubes.The charge diffusion coefficients of transition metal complexes polymer poly [Ni（salen）] and poly [Ni（salphen）]electrodes are 1.23×10^（-8）cm^2/s,1.86×10^（-9）cm^2/s,respectively.The specific capacitances of poly [Ni（salen）] and poly[Ni（salphen）] are 66.6 F/g、106.3 F/g at a current density of 0.05 m A/cm^2,respectively.The capacitance and electrochemical properties of transition metal complexes polymer with tetradentate N_2O_2Schiff-base ligand poly[Ni（salphen）] is better than that of poly[Ni（salen）].