title: Universal Features of Electron Dynamics in Solar Cells with TiO2 Contact: From Dye Solar Cells to Perovskite Solar Cells.
abstract: The electron dynamics of solar cells with mesoporous TiO2 contact is studied by electrochemical small-perturbation techniques. The study involved dye solar cells (DSC), solid-state perovskite solar cells (SSPSC), and devices where the perovskite acts as sensitizer in a liquid-junction device. Using a transport-recombination continuity equation we found that mid-frequency time constants are proper lifetimes that determine the current-voltage curve. This is not the case for the SSPSC, where a lifetime of ∼1 μs, 1 order of magnitude longer, is required to reproduce the current-voltage curve. This mismatch is attributed to the dielectric response on the mid-frequency component. Correcting for this effect, lifetimes lie on a common exponential trend with respect to open-circuit voltage. Electron transport times share a common trend line too. This universal behavior of lifetimes and transport times suggests that the main difference between the cells is the power to populate the mesoporous TiO2 contact with electrons.
authors.affiliation: Área de Química Física, Universidad Pablo de Olavide , 41013 Sevilla, Spain.
authors.forename: Anna
authors.initials: A
authors.lastname: Todinova
authors.affiliation: Área de Química Física, Universidad Pablo de Olavide , 41013 Sevilla, Spain.
authors.forename: Jesús
authors.initials: J
authors.lastname: Idígoras
authors.affiliation: Abengoa Research , C/Energía Solar no. 1, Campus Palmas Altas, 41014 Sevilla, Spain.
authors.forename: Manuel
authors.initials: M
authors.lastname: Salado
authors.affiliation: Abengoa Research , C/Energía Solar no. 1, Campus Palmas Altas, 41014 Sevilla, Spain.
authors.forename: Samrana
authors.initials: S
authors.lastname: Kazim
authors.affiliation: Área de Química Física, Universidad Pablo de Olavide , 41013 Sevilla, Spain.
authors.forename: Juan A
authors.initials: JA
authors.lastname: Anta
keywords: TiO2; dye-sensitized solar cell; perovskite; solar cells