Effect of the linkage position in ruthenium dyes on the photoelectrochemical perfomance

A series of newly designed Ru-dyes constructed with [Ru(bpy)(bpp)Cl]+ (bpp = 2,6-bis(N-pyrazolyl)pyridine, bpy = bipyridine) as template were evaluated by studying the frontier molecular orbital energy, charge distribution, absorption spectrum, light harvesting efficiency, as well as photogenerated current density by using (time-dependent) density functional theory. The calculation results reveal that the light harvesting efficiency and current density are enhanced with only one linkage group attached onto the 4 site of pyridine ligand. Mounting the linkage groups to 3 or 3′ position on pyridine ligand introduces super strong UV absorption.