Heteroleptic ruthenium complex containing substituted triphenylamine hole-transport unit as sensitizer for stable dye-sensitized solar cell

Abstract

A new heteroleptic ruthenium(II) complex cis-di(thiocyanato)(4,4′-dicarboxylic acid-2,2′-bipyridine)(4,4′-bis[(triethylene glycol methyl ether)(ditolylamine phenyl)ethenyl]-2,2′-bipyridine) ruthenium(II) (Ru-TPA-EO-NCS) was synthesized and characterized as a sensitizer for dye-sensitized solar cell application. The ligand contributes to enhance the light harvesting yield rendering a high short-circuit current density of 18.3mA/cm2 at full sun condition (1000W/m2) leading to an efficient dye-sensitized solar cell. The dye is explored for solid-state solar cell based on 2.0μm thick thin TiO2 film with organic hole transport material, Spiro-MeOTAD and it turns out to render 3.3% at full sun. The stability of DSCs is an important aspect for their commercialization. In this respect, the dye in conjunction with a solvent-free electrolyte exhibited a good long-term stability without a drop of the current density.