Acta Phys. -Chim. Sin. ›› 2015, Vol. 31 ›› Issue (5): 866-876.doi: 10.3866/PKU.WHXB201503254

• THEORETICAL AND COMPUTATIONAL CHEMISTRY • Previous Articles     Next Articles

Theoretical Study of Hemicyanine Dye as a Dye-Sensitized Solar Cell Light-Absorbing Material

LI Hui-Xue1, ZUO Guo-Fang1, LI Zhi-Feng1, WANG Xiao-Feng1, ZHENG Ren-Hui2   

  1. 1 College of Chemical Engineering and Technology, Tianshui Normal University, Tianshui 741001, Gansu Province, P. R. China;
    2 State Key Laboratory for Structural Chemistry of Unstable and Stable Species, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, P. R. China
  • Received:2015-02-27 Revised:2015-03-25 Published:2015-05-08
  • Contact: LI Hui-Xue E-mail:li_hx2001@126.com
  • Supported by:

    The project was supported by the National Natural Science Foundation of China (21465021, 21463023), Key Project of Ministry of Education, China (211189), Natural Science Foundation of Gansu Province, China (1208RJZE139), and Program of Gansu Provincial University for Leaders of Disciplines in Science, China (11zx-04).

Abstract:

We used first-principles calculations to investigate the photo-induced electron transfer (PIET) process of the hemicyanine-(TiO2)n complex ((TiO2)n-dye) for n=5, 9, 15. The geometries of the (TiO2)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 (kCS) and charge recombination rate constant (kCR) were calculated using Marcus theory. The calculated results showed that there were a cascade of electron transfer channels from the dye into the (TiO2)n cluster, which increases the kCS value. In contrast, the single channel of charge recombination decreases the kCR value, which is negligible compared with kCS, indicating that electron recombination is not favored.

Key words: Theoretical study, Hemicyanine dye, (TiO2)n cluster, Electron transfer

MSC2000: 

  • O641