Direct Comparison of Electron Transport and Recombination Behaviors of Dye-Sensitized Solar Cells Prepared Using Different Sintering Processes

作者：Li, Yuelong^*; Zhang, Xiaodan; Ko, Min Jae^*

来源：ACS Sustainable Chemistry and Engineering, 2018, 6(5): 7193-7198.

DOI：10.1021/acssuschemeng.8b01351

• Flexible dye-sensitized solar cell
• Electron transport and recombination
• Hot compression
• High-temperature sintering
• Impedance
• Photocurrent-voltage transient technique

Flexible dye-sensitized solar cells on plastic substrates have achieved a conversion efficiency of 8.6% with the hot compression technique (<150 degrees C). However, the value of efficiency is only 70% of that achieved using glass substrates with high-temperature sintering technique (500 degrees C). Investigating the origin of this difference is a critical step for further improving the performance of plastic dye-sensitized solar cells. In this study, an optimized ternary viscous titania paste without the addition of organic binders enables the fabrication of efficient dye-sensitized solar cells with a low-temperature process. Therefore, the electron-transport behavior of dye-sensitized solar cells can be directly compared with those prepared with the high-temperature sintering technique. In addition to the structural and optical differences, the hot compressed photoanode of dye-sensitized solar cells have an electron diffusion coefficient that is 2 times smaller and a recombination time that is 6 times shorter than those of the high-temperature sintered cells, suggesting inadequate interparticle connections and more recombination events. These results indicate that electron transport and recombination are still the key factors governing the performance of low-temperature fabricated dye-sensitized solar cells. Eventually, the flexible cell with an efficiency of 6.81% has been achieved on flexible indium tin oxide/polyethylene naphthalate substrate. Further improvements in advanced low-temperature processing or novel materials with minimized defect or grain boundaries are required.

• 出版日期2018-5
• 单位南开大学