Simulation of dye solar cells: Through and beyond one dimension

In this work we present a Computer Aided Design (CAD) software, called TiberCAD, to simulate Dye Sensitized Solar Cells (DSC). DSCs are particularly interesting devices due to their high efficiency (more than 11% on small area and 8% on large area) and long stability. Since their first development, much progress has been made in terms of efficiency, stability, lifespan and engineering of the device. However, the field of DSCs still lacks a complete model able to simulate the entire device over a general domain including all its components. In our model a driftdiffusion set of equations for the different charge carriers coupled to Poisson equation has been implemented within finite element method. The model takes into account also trap assisted transport for electrons in the mesoporous titanium dioxide with a phenomenological model derived from multi-trapping model. Three different applications of the code in 1, 2 and 3D are presented. The first 1D simulation is a study of correlation between physical parameters of the cell and energy conversion efficiency. A second application, 2D, discusses the effect on density and current distributions for different contacting of the cell and loss induced by the shadowing of metallic fingers. Finally, the third case, 3D, presents two different and innovative topologies for a DSC. A cell where contacts and illumination surface are completely decoupled and a DSC wrapped around an optical fiber.