染料敏化太阳电池相间电荷传输行为的机理研究

Characters of Charge Transport Behavior Between Interfaces in Dye-Sensitized Solar Cells

本文通过对染料敏化太阳电池(DSC)内半导体薄膜及电解液层电荷传输过程的数值模拟,借助纳米薄膜微结构参数(孔洞率)与微观动力学参数的内在联系,将多孔膜内电子传输过程与电解液中离子扩散过程有机结合,细致研究了相间电荷传输行为对DSC性能输出的影响.研究表明,对于固态/准固态等离子扩散系数较低的电池(传输受限体系),电解液中的电荷传输过程是必须考虑的重要因素.改善传输受限体系的性能输出,就要对电解液层厚度、孔洞率和碘浓度同时优化,而通常电解液层厚度的影响往往容易被忽略.

Herein,the characters of charge transport behavior between interfaces in dye-sensitized solar cells （DSC） and their further influence on cell performance is investigated.Numerical simulation is developed by the intrinsic connection between microstructure parameters and microcosmic dynamics constants.The interactional effect between electron transport in TiO2 films and ion transport in electrolyte is discussed particularly,which contributes us to further comprehend the working mechanism of DSC.It is found that the electron transport process in TiO2 films is seriously limited by ion diffusion process in electrolyte for solid-state/quasi-solid-state DSCs （transport-limited system）,whose ion diffusion coefficient is rather low.To enhance the performance of transport-limited system,all of the parameters,such as porosity of the films,thickness of the electrolyte layer and concentration of iodine need to be considered.