A novel dye (2TPA-R), contg. two triphenylamine (TPA) units connected by a vinyl group and rhodanine-3-acetic acid as the electron acceptor, is designed and synthesized successfully to reveal the working principles of org. dye in dye-sensitized solar cells (DSSCs). 2TPA and TPA-R, which consist of two TPA units connected by vinyl and a TPA unit linked with rhodanine-3-acetic acid, resp., are also synthesized as refs. to study the intramol. energy transfer (EnT) and charge transfer (ICT) processes of 2TPA-R in CH2Cl2 soln. and on a TiO2 surface. The results suggest that the intramol. EnT and ICT processes show a pos. effect on the performance of DSSCs. However, the flexible structure and less-adsorbed amt. of dye on TiO2 may make it difficult to improve the efficiency of DSSCs. This study on intramol. EnT and ICT processes acts as a guide for the design and synthesis of efficient org. dyes in the future.