染料敏化太阳电池中多相接触界面电子转移机制和动力学过程

Mechanisms of Electron Transfer and Dynamic Process at the Multiphase Interface in Dye Sensitized Solar Cell

采用电化学阻抗谱(EIS)研究了染料敏化太阳电池(DSC)中由导电玻璃、纳米多孔TiO2薄膜和电解质构成的多相复杂接触界面的电子转移机制和动力学过程.通过沉积聚合物薄膜简化多相接触界面结构,根据接触界面结构和电子转移途径的变化,分析了不同偏压下多相接触界面电子转移机制,构建与之对应的等效电路,获得了DSC内部各个主要接触界面的电子转移动力学常数.结果表明,通过外加偏压的控制和多相接触界面结构的简化,可以区别分析多相复杂接触界面电子转移机制与动力学过程.

The multiphase complex interface made up of the transparent conductive oxide substrate （TCO）, nano-porous TiO2 film and electrolyte was formed at the substrate of the anode in dye sensitized solar cell （DSC）. The mechanisms of electron transfer and dynamic process at this multiphase complex interface were investigated by electrochemical impedance spectroscopy（EIS）. The multiphase interface structure was simplified by an insulating layer which electropolymerized on the exposed TCO. According to changes of the contact interface structure and electron transfer pathway, the corresponding equivalent circuits were constructed. The interface electron transfer mechanism was analyzed and the electron transfer kinetic constants for the electron transfer across the main contact interracial were obtained at different bias. The results show that different mechanism of interracial electron transfer and kinetics process can be distinguished by adjusting the bias and simplifying the muhiphase interface structure.