Effect of the bridge substitution on the efficiency of dye-sensitized solar cells

We have designed and synthesized a novel D–π–A dye based on zinc porphyrin as the donor, cyanoacrylic acid as the acceptor and trans-bis(3,4-ethylenedioxythiophene)vinylene as the bridge. Under standard global AM 1.5 solar conditions, the Zn-porphyrin-2-EDOT sensitizer based cell gave a JSC of 7.28 mA cm−2, VOC of 0.438 V was obtained with a FF of 0.514, corresponding to an overall conversion efficiency η = 1.64%. The reasons for this low efficiency are analyzed to try to develop knowledge for future dye designing.