%A LI Hui-Xue, ZUO Guo-Fang, LI Zhi-Feng, WANG Xiao-Feng, ZHENG Ren-Hui
%T Theoretical Study of Hemicyanine Dye as a Dye-Sensitized Solar Cell Light-Absorbing Material
%0 Journal Article
%D 2015
%J Acta Phys. -Chim. Sin.
%R 10.3866/PKU.WHXB201503254
%P 866-876
%V 31
%N 5
%U {http://www.whxb.pku.edu.cn/CN/abstract/article_29082.shtml}
%8 2015-05-08
%X We used first-principles calculations to investigate the photo-induced electron transfer (PIET) process of the hemicyanine-(TiO_{2})_{n} complex ((TiO_{2})_{n}-dye) for *n*=5, 9, 15. The geometries of the (TiO_{2})_{n}-dye in the ground state were optimized using density functional theory (DFT) and their excited states were investigated using the time-dependent DFT (TDDFT) method. The excited energies, which were calculated using the longrange- corrected functionals, CAM-B3LYP and ωB97X-D, were in good agreement with the experimentally observed values. The wave functions based on DFT were used to calculate the charge transfer integrals by the generalized Mulliken-Hush (GMH) approach. In addition, the photo-induced charge separation rate constant (*k*_{CS}) and charge recombination rate constant (*k*_{CR}) were calculated using Marcus theory. The calculated results showed that there were a cascade of electron transfer channels from the dye into the (TiO_{2})_{n} cluster, which increases the *k*_{CS} value. In contrast, the single channel of charge recombination decreases the *k*_{CR} value, which is negligible compared with *k*_{CS}, indicating that electron recombination is not favored.