A novel dye coating method for N719 dye-sensitized solar cells

In dye-sensitized solar cells (DSSCs), dye coating is one of the important factors in the fabrication process. Dye coating takes more than several hours in the conventional methods when Ru-based dyes, especially N719, the main dye for DSSC applications, are applied. In this paper, we applied a new coating system to maximize the adsorption reaction between the dye and TiO2 nanocrystalline surface. Applied solvents are from mono alcohol to triols with various temperatures and concentrations of the dye. According to our experiments, dye coating time can be shortened down from several hours to 3 min. To compare the new system to the conventional system, various analysis tools were applied for further investigation. The new solvent system with ethylene glycol, gives many advantages such as saving solvent usage, short coating time, and easy procedure for mass fabrication without toxicity.

► In this study, we developed a new method with ethylene glycol to coat dyes within 3 min for dye-sensitized solar cells.
► The new solvent ethylene glycol is viscous, and non-volatile at high temperature.
► Therefore, it can be easily applied to deliver dyes on porous TiO2 surface at high temperature without a container.
► It takes only 3 min to fully cover the working electrode with efficiency up to 9.17%.