Substitution of Carbazole Modified Fluorenes as π-Extension in Ru(II) Complex-Influence on Performance of Dye-Sensitized Solar Cells

Scheme 1

Synthesis route for BPFC; (i) N-bromosuccinimide, acetone at 60°C 3 hours; (ii) bromobutane, powdered KOH, KI and DMSO, RT 12 hours; (iii) n-BuLi, Triisopropyl borate, THF, 2M HCl, −78°C, 4 hours; (iv) 4,4′-dibromo-2,2′-bipyridine, Ba(OH)₂⋅8H₂O, Pd(PPh₃)₄, dioxane/water, reflux, 24 hours; (v) Iodine, conc. H₂SO₄, HIO₄, H₂O, AcOH, 80°C, 4 hours; (vi) 3,6-di-tert-butyl-9H-carbazole, Cu Bronze, K₂CO₃, Nitrobenzene, reflux, 24 hours; (vii) [Ru(p-cymene)₂Cl₂]₂, DMF, 60–70°C; (viii) 4,4′-dicarboxy-2,2′-bipyridine, NH₄NCS, DMF, 8 hours, reflux.