Synthesis and characterization of β-pyrrolic functionalized porphyrins as sensitizers for dye-sensitized solar cells

New β-pyrrolic functionalized porphyrins with donor-π-acceptor character were synthesized and characterized as dye sensitizers for dye-sensitized solar cells. Two types of π-conjugated spacers, namely benzene and thiophene rings, with cyanoacrylic acid as an acceptor were linked to the porphyrin ring at the β-pyrrolic position. These porphyrins showed high thermal and electrochemical stability. As sensitizers, the porphyrin dye bearing a thiophene ring as the π-conjugated spacer gave better cell performance with a short-circuit photocurrent density (Jsc) of 4.57 mA cm−2, an open-circuit voltage (Voc) of 0.59 V, and a fill factor (ff) of 0.59, corresponding to an overall conversion efficiency (η) of 1.94%.