▎ 摘　　要

Three D-A'-p-A type of metal-free organic sensitizers, which are based on naphtho [2,3-d] [1-3] triazole entity as auxiliary acceptor and several dithienoheterocycles (cyclopentadithiophene, dithieno[3,2-b:2',3'-d]silole, dithieno[3,2-b:2',3'-d]pyrrole) as p-conjugated bridge, are investigated using density functional theory (DFT)/time-dependent DFT methods. First, the influence of different p-bridges on the photovoltaic properties in three dyes is analyzed by mainly studying geometry structures, spectral characteristics, electron injection, dye regeneration, and charge difference density to explain highest performance of HJL-3. Second, molecular design of introducing graphene quantum dots (GQDs) is carried out, and the results find that HJL-3@GQDs display better photoelectric performance because GQDs have a positive impact on some parameters (such as light-harvesting efficiency, electron injection amounts, dipole moment, and so on) upon introducing GQDs. This work provides a reasonable explanation for the experiment and a way to regulate performance of dye-sensitized solar cells.