Coupling of photoactive transition metal complexes to a functional polymer matrix

Abstract

Conductive polymers represent a promising alternative to semiconducting oxide electrodes typically used in dye-sensitized cathodes as they more easily allow a tuning of the physicochemical properties. This can then also be very beneficial for using them in light-driven catalysis. In this computational study, we address the coupling of Ru-based photosensitizers to a polymer matrix by combining two different first-principles electronic structure approaches. We use a periodic density functional theory code to properly account for the delocalized nature of the electronic states in the polymer. These ground state investigations are complemented by time-dependent density functional theory simulations to assess the Franck-Condon photophysics of the present photoactive hybrid material based on a molecular model system. Our results are consistent with recent experimental observations and allow to elucidate the light-driven redox chemical processes -eventually leading to charge separation -in the present functional hybrid systems with potential application as photocathode materials.

Prediction of strong solvatochromism in a molecular photocatalyst

“…1 Recent years have witnessed an increased understanding of the mechanisms operative in photochemical molecular devices which combine a photosensitizer and a catalyst connected by an electron relay. [2][3][4][5][6][7][8][9] The operation of such molecular devices requires the presence of solvents, and as many molecular complexes are insoluble in aqueous media, often organic solvents are used. 5 Although it is known that the activity of photocatalysts is influenced by the properties of the solvent, 6 it is fair to say that a systematic understanding of this influence is still lacking.…”