Theoretical studies on structural and spectroscopic properties of photoelectrochemical cell ruthenium sensitizers, derivatives of AR20

摘要

Special efforts were devoted to improve the absorption behavior of AR20 in visible region. Density functional theory (DFT)-based approaches were applied to explore the electronic structure properties of AR20 and its derivatives. Time-dependent DFT results indicate that the ancillary ligand controls the molecular orbital (MO) energy levels and masters the absorption transition nature. The deprotonation of anchoring ligand not only affects the frontier MO energy levels but also determines the energy gaps of highest occupied MO-lowest unoccupied MO (LUMO) and LUMO-LUMO+1. Introducing thiophene groups into ancillary ligands would enhance the efficiency of the final dye-sensitized solar cell (DSSC). The absorption intensity of the thiophene substituted derivatives of AR20 is irrelevant with environment circumstance change, such as pH value. This special nature prognosticates the thiophene-substituted derivatives of AR20 which would have a broad application in DSSC.