电活性质点Fe^2^+离子在六氰亚铁钒薄膜中的传输

电活性质点Fe^3^+可穿透六氰亚铁钒薄膜在玻璃碳基体电极表面于较负电位处直接氧化, 也可经VHF膜中氧化还原点位的媒介在较正电位处理膜-溶液界面及膜内部发生催化氧化. 两个过程分别在用VHF修饰过的旋转GC电极上的伏安曲线中产生, 可明确分辨的第一波和第二波. 第一波的极限电流受Fe^2^+离子在溶液中和膜中的扩散速率控制.VHF薄膜对Fe^2^+离子的透过能力, kDm/d, 为10^-^3-10^-^2cm.s^-^1数量级, 随膜厚度增大而减小, 不随溶液中Fe^2^+离子浓度改变.

Transport of electroactive species Fe^2^+ through thin films of vanadium hexacyanoferrate

The electroactive species Fe2+ can be transported easily through the thin films of KVFe(CN)6 (I) to the underlaying glassy C electrode surface to be oxidized directly at less pos. potential, and it can also be oxidized at the film at more pos. potential by means of redox sites in the film. These 2 processes yield clearly distinguished sequential 1st and 2nd waves in steady-state current-potential curves resulting from use of a rotating-disk electrode. The plateau current of the 1st wave is limited by the diffusion rate of Fe2+, both in the solution and in the film. The permeability parameter, kDm/d, of the I film to Fe2+ is of the order of 10-3-10-2 cm/s, which decreases linearly with an increase in film thickness and remains constant when the bulk concentration of Fe2+ in the solution varies.