Computational Investigations on Organic Sensitizers for Dye-Sensitized Solar Cells

A comprehensive overview on the main applications of state-of-the-art computational methodologies to the simulation of Dye-Sensitized Solar Cells (DSSCs) based on metal-free organic dyes is reported. The presented results cover two crucial aspects that should be carefully taken into account in the design of novel and highly efficient sensitizers, namely the electronic structure of the dye (spectroscopic and redox properties) and its interactions with the TiO2 surface. Concerning the electronic structure calculations, our results demonstrate that a proper TDDFT formulation can successfully describe the excited state properties of a series of organic dye sensitizers, yielding results of comparable quality to high-level correlated ab initio calculations. Our work on the adsorption and aggregation of organic dyes on TiO2 surfaces show that the adopted integrated computational strategies and models can realistically simulate and predict the interaction of the dyes with the TiO2 substrate, thus underlying the main factors responsible of DSSC efficiency.