染料敏化太阳电池内部光路折转对电子传输特性的影响

Effect of light path folding on the properties of electron transport in dyesensitized solar cell

基于染料敏化太阳电池(DSC)光阳极的反射层结构,建立了含有光路折转的电子连续性方程.计算和分析了不同吸收条件和反射条件下的调制光电流频率响应特性,研究了DSC内部光路折转对电子传输特性的影响.通过不同膜厚的强度调制光电流谱测试表明,建立的模型反映了DSC内部光路折转时调制光电流频率响应.动力学研究结果表明,在含有反射层的DSC中,电子传输动力学过程依赖于光吸收系数、薄膜厚度以及大颗粒反射能力等因素.DSC内部光路折转导致较深陷阱被电子填充,缩短了电子在陷阱中的停留时间,减小了俘获/脱俘影响,使电子传输过程加快.

In this paper, an electron continuity equation with light path folding is developed based on the reflection structure of photoanode in a dye sensitized solar cell （DSC）. The characteristics of modulated photocurrent frequency response are calculated, and the effects of light path folding on electron transport property are studied under different absorption and reflection conditions. Intensity modulated photoeurrent spectroscopy measurements show that the established model reflectes the actual characteristic of the response to modulated photocurrent frequency when the light path is folded inside the DSC. The kinetic of electron transfer process depends on the light absorption coefficient, film thickness and large particle reflection ability and other factors in DSC with reflector structure. The deep trap is filled and residence time of electron in trap is shortened. It is attributed to the fact that the light path folding reduces the effect of trap/detrap and accelerates the electron transportation.