Multiscale Simulation of Dye-Sensitized Solar Cells Considering Schottky Barrier Effect at Photoelectrode

概要

論文の詳細を見る
The effect of the TiO2/transparent conducting oxide (TCO) interface in a photoelectrode of a dye-sensitized solar cell (DSSC) on its cell performance was investigated using our multiscale simulator, in which we had added a calculation of the voltage loss derived from the Schottky barrier height (SBH) at the TiO2/TCO interface to our previous simulator. We treated the TiO2/TCO interface as a series connection of a Schottky diode of metal/n-type semiconductor. The thermionic-emission theory was applied to describe the electron transfer and the voltage loss at the TiO2/TCO interface. The accuracy of the prediction of the current density--voltage ($J$--$V$) characteristics of a DSSC employing the cis-dithiocyanato-bis(2,2$'$-bipyridyl-4,4$'$-dicarboxylic acid)-ruthenium(II) (N3 dye) was improved compared with that obtained by our previous simulator. The effects of the SBH on the open circuit voltage ($V_{\text{OC}}$) and the maximum power output ($P_{\text{max}}$), as well as the $J$--$V$ characteristics, of the DSSC were discussed. Our results suggest that a TCO with the $\mathrm{SBH}\leq 0.5$ is suitable for a DSSC.
2011-04-25