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

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 18.3 mA/cm2 at full sun condition (1000 W/m2) leading to an efficient dye-sensitized solar cell. The dye is explored for solid-state solar cell based on 2.0 μm 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.

Graphical abstractA novel heteroleptic ruthenium(II) complex substituted with dimethylphenylaniline units incorporating ethylene glycol as donor ligand as a good sensitizer for the dye-sensitized solar cells leading to a promising stability and conversion efficiency.Figure optionsDownload full-size imageDownload as PowerPoint slideHighlights► A novel heteroleptic ruthenium(II) complex contains substituted triphenylamine unit. ► The complex is used as a sensitizer for the dye-sensitized solar cells. ► Three different redox relays, liquid, solid and solvent-free redox are incorporated. ► A promising stability of the device with no change in photocurrent is observed.