The suzuki-heck polymerization as a tool for the straightforward obtainment of poly(fluorenylene-vinylene) sensitizers for dye-sensitized solar cells

This article describes the synthesis and properties of the first poly(arylene-vinylene)-based sensitizers for application in dye-sensitized solar cells (DSSC). The polymers were prepared by the Suzuki-Heck copolymerization of potassium vinyltrifluoroborate (PVTB) with a mixture of dibromoaryl comonomers designed to obtain macromolecules able to bind on to the photoelectrode by means of carboxyphenylene units. The copolymerization reactions were carried out in the presence of an excess of PVTB to lower the molecular weights of the polymers, which were obtained as soluble materials. The polymers poly[(9,9-didodecyl-2,7-fluorenylene)-vinylene-co-(carboxy -2,5-phenylenel-vinylene] (P1), poly[(9,9-didodecyl-2,7-fluo-renylene)-vinylene-co-(carboxy-2,5-phenylene)-vinylene-co-(4,7-benzothiadiazolylene)-vinylene] (P2), and poly[(9,9-didodecy12,7-fluorenylene)-vinylene-co-(carboxy-2,5-phenylene)-vinylene- co-2,5-thienylene-vinylene] (P3) were used in DSSC devices, obtaining conversion efficiencies up to 0.88% (P3)