Probing the Limits: Ultraslow Diffusion and Heterogeneous Electron Transfers in Redox Polyether Hybrid Cobalt Bipyridine Molten Salts
作者:Joseph C. Crooker、Royce W. Murray
DOI:10.1021/ac000231o
日期:2000.7.1
self-diffusion coefficients and of heterogeneous Co(II/III) electron-transfer rate constants (ko) in undiluted molten salts of three cobalt tris(bipyridine) perchlorate complexes in which the bipyridine ligands are "tailed" with poly(propylene oxide) and poly(ethylene oxide) oligomers. The self-diffusion coefficients are measured with potential step chronoamperometry and range from 10(-12) to 10(-17) cm2/s
本文描述了微电极伏安法测量的三联三(联吡啶)高氯酸钴配合物的未稀释熔融盐中的自扩散系数和非均相Co(II / III)电子传递速率常数(ko)与聚环氧丙烷和聚环氧乙烷低聚物。自扩散系数通过电位阶跃计时电流法测量,范围为10(-12)至10(-17)cm2 / s,而准可逆反应速率常数使用循环伏安法和较小的电位阶跃进行测量,范围为10 (-7)至10(-12)cm / s。ko测量值是不寻常的,因为当速率常数变小时,由于同时降低了自扩散率,反应保持准可逆。此外,测量结果是 面对不平衡的电阻(兆欧到千兆欧),可以通过微电极特性和小扩散率的组合来实现。自扩散和ko值最小的熔体是在低于其标称玻璃化转变温度且处于分子尺度扩散曲线范围内的温度下。