Modeling and simulation for dye-sensitized solar cells

We developed an equivalent circuit for dye-sensitized solar cells, which provides a more accurate presentation and a better fit to the experimental I-V curves and Nyquist plots than earlier literature results, as verified by simulation. A simple expression for the estimation of the Warburg coefficient from the experimental Nyquist plot is also proposed in this letter. The simulated I-V curves and Nyquist plots are in good agreement with the experimental data. The interfacial charge transfer and recombination losses at the oxide/dye/electrolyte interface are found to be the most influential factor on the overall conversion efficiency.