1. The Abdus Salam International Centre for Theoretical Physics (ICTP), Strada Costiera 11, 34151 Trieste, Italy;2. Department of Physics, Faculty of Sciences, Marien Ngouabi University, P.O. Box 69, Brazzaville, Congo;3. CNR‐IOM DEMOCRITOS Simulation Center, 34136 Trieste, Italy
Abstract:
We present a computational study based on time‐dependent density functional theory of the optical absorption spectra of TiO2 nanowires sensitized with organic dye molecules. We concentrate on catechol and squaraine dyes. For those molecules, we compute adsorption geometries and energies and investigate the optical properties of the combined dye– nanowire system. We find that although the molecules have qualitatively different optical spectra in the gas phase, both lead to an enhancement of the absorption in the visible frequency range when adsorbed on a nanowire.