Quantum chemistry study on absorption spectra, electronic and electrical properties of organic dye on anatase(001)

J Nanosci Nanotechnol. 2010 Apr;10(4):2434-43. doi: 10.1166/jnn.2010.1398.

Abstract

As the most reactive surface, the stoichiometric O-bridge terminated anatase(001) surface attracted considerable attentions in many application fields. The interfacial electron transfer in dye-sensitized anatase(001) plays a principal role in a variety of photoinduced reactions. In the present work, the UV-vis absorption spectrum of TiO2 bulk and different surface models were calculated by means of tight-binding quantum chemical molecular dynamics program "Colors-excite" for the first time. The thickness dependence on electronic and electrical properties of anatase(001) surface was achieved. The anatase(001) surface with a thickness of 1.0 nm shows excellent electronic and electrical properties. Moreover, the most suitable binding mode (dissociative adsorption) and absorption spectra of perylene with acrylic acid (PAA) on the optimum anatase(001) were investigated. A significant red-shift was observed from the UV-vis absorption spectrum of PAA/anatase(001) system. The red-shift occurring when PAA adsorbed on anatase(001) surface suggests that PAA/anatase(001) may be potential candidate for dye-sensitized solar cell. This study also proposed an effective computational tool "Colors-excite" to study of the electronic excitation properties for both molecular and periodic systems.