Two new mixed ligand ruthenium(II) complexes, Ru(dcbpy)^(LL)(NCS) 2 [where dcbpy=4,4′ dicarboxyl 2,2′ bipyridine, LL=4,4′ bis( N methyl anilinomethyl) 2,2′ bipyridine (1) or 4 methyl 4′ N met...Two new mixed ligand ruthenium(II) complexes, Ru(dcbpy)^(LL)(NCS) 2 [where dcbpy=4,4′ dicarboxyl 2,2′ bipyridine, LL=4,4′ bis( N methyl anilinomethyl) 2,2′ bipyridine (1) or 4 methyl 4′ N methyl anilinomethyl 2,2′ bipyridine (2)], were synthesized, and the photophysical properties of these complexes were studied. The metal to ligand charge transfer (MLCT) transitions of these complexes exhibited solvatochromic effect due to the existence of NCS ligands. The MLCT energies also strongly depend on the pH values of the solutions because of protonation and deprotonation of the carboxyl groups. The p K a values of the ground state, 4 0 for 1 and 3 8 for 2, were obtained from the titration curves. The photoelectrochemical properties of 1 and 2 as sensitizers in sandwich type solar cells have been studied. Complex 1 exhibited better photoelectrochemical behavior than complex 2 as expected. It was proved that the design of mixed ligand complex by introducing electron donating group in one of the ligands should be a promising approach.展开更多
文摘Two new mixed ligand ruthenium(II) complexes, Ru(dcbpy)^(LL)(NCS) 2 [where dcbpy=4,4′ dicarboxyl 2,2′ bipyridine, LL=4,4′ bis( N methyl anilinomethyl) 2,2′ bipyridine (1) or 4 methyl 4′ N methyl anilinomethyl 2,2′ bipyridine (2)], were synthesized, and the photophysical properties of these complexes were studied. The metal to ligand charge transfer (MLCT) transitions of these complexes exhibited solvatochromic effect due to the existence of NCS ligands. The MLCT energies also strongly depend on the pH values of the solutions because of protonation and deprotonation of the carboxyl groups. The p K a values of the ground state, 4 0 for 1 and 3 8 for 2, were obtained from the titration curves. The photoelectrochemical properties of 1 and 2 as sensitizers in sandwich type solar cells have been studied. Complex 1 exhibited better photoelectrochemical behavior than complex 2 as expected. It was proved that the design of mixed ligand complex by introducing electron donating group in one of the ligands should be a promising approach.
