Photo-induced charge transfer in defect-free (TiO2)15 nanoparticles and charge transfer from carotenoid to (TiO2)15b nanoparticle in carotenoid–(TiO2)15b complex used for solar cell

Photo-induced charge transfer process between the carotenoids and (TiO2)15b was theoretically studied with quantum chemical methods, and the charge transfer information of the carotenoid–(TiO2)15 complex were visualized using the charge difference density method. Calculated results show the strongest absorption wavelength is located at 606 nm. Electron transfer in the isolated (TiO2)15 was also analyzed in some detail. For 15b (C2v), electrons transfer from one layer to the other layer; while for 15a (C2v), electrons transfer from the outer O atoms to the inter Ti atom.