Computational studies on optoelectronic and charge transfer properties of some perylene-based donor-[pi]-acceptor systems for dye sensitized solar cell applications

We report DFT studies on some perylene-based dyes for their electron transfer properties in solar cell applications. The study involves modeling of different donor-π-acceptor type sensitizers, with perylene as the donor, furan/pyrrole/thiophene as the π-bridge and cyanoacrylic group as the acceptor. The effect of different π-bridges and various substituents on the perylene donor was evaluated in terms of opto-electronic and photovoltaic parameters such as HOMO-LUMO energy gap, λmax, light harvesting efficiency(LHE), electron injection efficiency (Øinject), excited state dye potential (Edye*), reorganization energy(λ), and free energy of dye regeneration ([Delta]G d y e R e g e n). The effect of various substituents on the dye-I2 interaction and hence recombination process was also evaluated. We found that the furan-based dimethylamine derivative exhibits a better balance of the various optical and photovoltaic properties. Finally, we evaluated the overall opto-electronic and transport parameters of the TiO2-dye assembly after anchoring the dyes on the model TiO2 cluster assembly.