Stepped light-induced transient measurements of photocurrents and photovoltages in dye-sensitized solar cells: Application for the effects of a TiO2 buffer layer

초록

The technique of stepped light-induced transient measurements of photocurrents and photovoltages (SLIM-PCV) was applied to measure the diffusion coefficients (De) and lifetimes ( ) τ of electrons in d)esensitized solar cells (DSSCs). In this method, the power of a cw laser irradiating to the DSSCs was decreased abruptl) b) ~3% with a function generator, and temporal variations of the transient photocurrents and photovoltages were measured, from which the De and τ values were e tracted. This method has a much simpler setup than the pulsed light-induced method and takes less time to obtain the deca) curves with a reasonable signal-to-noise ratio. We applied the SLIM-PCV to investigate the effects of a TiO2nanoporous buffer la)er on the performances of DSSCs, and found that the buffer layer increases the diffusion coefficients and lifetimes of electrons in d)e-sensitized solar cells.