A DFT/TD-DFT investigation on the e fficiency of new dyes based on ethyl red dye as a dye-sensitized solar cell light-absorbing material

摘要

The electronic, redox and photoelectrical properties of the novel series dyes are designed based on ethyl red dye as material sensitizers of dye sensitized solar cells. The ground and excited state characteristics of the all dyes before and after absorbed on TiO2 have been investigated using the DFT and TDDFT-B3LYP methods with 6-31++G (d,p) on a separate dye and Lanl2DZ basis set for a complex system containing the dye-oxide couple (Ti(OH)(3)H2O). The results for the geometers, total dipole moment, open circuit voltage, highest occupied molecular orbital (HOMO) level, lowest unoccupied molecular orbital (LUMO) level and their distribution, energy gaps, have been analyzed. Furthermore, the analysis of the absorption process of the dyes on the model (Ti(OH)(3)H2O) has reported the electron injection from the dyes to TiO2 surface. In general, the calculation indication of all dyes in the present study show excellent photoelectric conversion efficiency and can be potentially good photosensitizers in DSSC in comparison with ethyl red dye. Additionally, there is a possibility the electron injection process occurrence from each studied dye to the conduction band of TiO2 and the subsequent regeneration. Therefore, these properties suggest that these new materials behave as better applicants for organic solar cells. Moreover, they provide the results of rational molecular design followed by a survey of photophysical properties to be used as a valuable reference for the synthesis of photo-efficient dyes for DSSCs.