Determination of the Electron Lifetime in Nanocrystalline Dye Solar Cells by Open‐Circuit Voltage Decay Measurements

Fate of electrons: Kinetic measurements of open-circuit voltage decay in nanocrystalline TiO2 dye-sensitized solar cells reveal major features of the electron lifetime and recombination mechanisms in these solar cells. The lifetime dependence on the photovoltage is exponential in broad terms (see picture), ranging from three decades to 20 ms to 20 s, when the photovoltage decreases by about 0.6 V.