Differences in characteristics of dye-sensitized solar cells containing acetonitrile and ionic liquid-based electrolytes studied using a novel model

A performance simulation model of dye-sensitized solar cells including a “bulk” electrolyte layer separated from a TiO2 layer has been presented. The calculation results with this novel model agree well with experimental results, which indicates the importance of considering the bulk electrolyte layer in theoretical models. The model allows us to specify the diffusion coefficients of ionic species in nano-pores of the TiO2 layer and in the bulk electrolyte layer separately, and the importance of ionic diffusions in each layer is discussed. We further clarify the difference between ionic liquid-type cells and acetonitrile type cells, and discuss the important issues for increasing the efficiencies in cells containing ionic liquid-based electrolytes.