Novel fluorous amphiphilic heteroleptic ru-based complexes for a dye-sensitized solar cell: The first fluorous bis-ponytailed amphiphilic Ru complexes

摘要

A new series of amphiphilic heteroleptic ruthenium(II) sensitizers with a fluorous bis-ponytailed bipyridine ancillary ligand, [Ru(H_2dcbpy)(4, 4′-bis(R_fCH_2OCH_2)-2,2′-bpy)(NCS) _2] [where R_f = HCF_2CF_2 (CT4), C _3F_7 (CT7), and HCF_2CF_2CF _2CF_2 (CT8)], have been synthesized and fully characterized by UV/vis, visible emission, NMR, fast atom bombardment mass spectrometry, and cyclic voltammetric studies. Dye-sensitized solar cells (DSCs) based on these dyes exhibit efficiencies comparable with that of the standard cell based on N719. The conversion efficiency of a CT7- or CT8-based DSC is ～9% higher than that of Z907 with a nonfluorous bis-ponytailed bipyridine ancillary ligand. The fluorous chains were found to increase the dye density on TiO_2 and to help to suppress the dye desorption.