Theoretical study on the electronic absorption spectra and molecular orbitals of ten novel ruthenium sensitizers derived from N3 and K8

Ten novel sensitizer candidates Ru2, Ru4, Ru5, Ru6, Ru7, Ru8, Ru9, Ru10, Ru11 and Ru12 derived from the sensitizers N3 and K8 were designed and studied using the density functional theory and time-dependent density functional theory calculations. The influences of the CC double bonds between the carboxyl groups and the bipyridine ring as well as the numbers and positions of the –CN groups adjacent to the carboxyl groups on the properties of the sensitizer candidates were discussed. The energy levels and the spatial distributions of the frontier molecular orbitals as well as the electronic absorption spectra of these complexes were compared with those of N3 and K8. Ru10 and Ru7 were found promising to provide superior photon-to-current conversion efficiency to those of N3 and K8 in ruthenium complex sensitized solar cells.

Graphical abstractFigure optionsDownload full-size imageDownload high-quality image (94 K)Download as PowerPoint slideResearch highlights▶ Ten novel sensitizers derived from N3 and K8 were theoretically studied. ▶ The influences of CC on the properties of the sensitizers were discussed. ▶ The influences of –CN groups on the properties of the sensitizers were discussed. ▶ Ru10 and Ru7 were found promising to be superior to N3 and K8.