Novel D-π-A porphyrin dyes with different alkoxy chains for use in dye-sensitized solar cells

A series of novel zinc porphyrin dyes which are featured with a D-π-A structure have been designed and synthesized for use in dye-sensitized solar cells (DSSCs). The influences of different hydrophobic hydrocarbon chains (none, butoxy, octoxy groups) attached at the porphyrin meso-aryl group on the molecules' photophysical and electrochemical properties, as well as on the photovoltaic performance of the corresponding DSSCs were investigated systematically. The best performance was realized for the cell sensitized with the porphyrin (LP-2) containing a n-butoxy chain on the meso-aryl group and with the acrylic acid as the acceptor. The optimized power conversion efficiency of LP-2 reaches 6.04% with an open-circuit voltage of 730 mV, a short-circuit current density of 11.67 mA cm−2, and a fill factor of 0.71.