A novel Ru (II) complex with high absorbance coefficient: efficient sensitizer for dye-sensitized solar cells

In this paper, a new sensitizer, Ru(4,4′-dicarboxy(phenylethenyl)-2,2′-bipyridine) (4,4′-bis(2-(4-tert-butyloxyphenyl) ethenyl)-2,2′–bipyridine) (NCS)₂ with high absorbance coefficient denoting AJ-01, is introduced and its application in dye-sensitized solar cells (DSSCs) is investigated. The synthesized dye was characterized via various analytical methods, such as ¹HNMR, ¹³CNMR, and UV–vis spectroscopic methods, and finally, it was utilized as a visible-light sensitizer in DSSCs. The AJ-01 photovoltaic performances were compared with that of N-719 as a commonly used sensitizer and were evaluated under similar conditions. UV–Vis absorption spectra for the AJ-01 sensitizer were also showed that the molar extinction coefficients much higher than the N-719 sensitizer at the peak wavelengths of the new sensitizer. Furthermore, Ab initio calculations were used to clarify the electronic properties and the role of the anchoring ligands at the rate of electron transfer to TiO₂. The photovoltaic parameters of the AJ-01 sensitizer cell show an open-circuit voltage (Voc) of 0.764 V, short-circuit current density (Jsc) of 20.11 mA cm⁻² and fill factor (F.F.) of 0.55, and a power conversion efficiency of 8.4%.