Porphyrin containing lipophilic amide groups as a photosensitizer for dye-sensitized solar cells

Abstract

In this study, synthesis and investigation of a novel zinc-porphyrin derivative bearing C₂₄-containing amide groups for potential use in dye-sensitized solar cells (DSSCs) are presented. According to absorption spectra and electrochemical data, the target porphyrin has appropriate highest occupied molecular orbital (HOMO) and lowest unoccupied molecular orbital (LUMO) energy levels. The device studies revealed that the DSSCs based on the target porphyrin exhibited higher light harvesting efficiency in the Q-band region and an increased photocurrent, compared to the DSSCs based on a benchmark derivative bearing no alkyl amide groups on the meso-phenyl substituents. The optimum DSSC based on the target porphyrin gave a short-circuit photocurrent density (J_sc), an open-circuit voltage (V_oc) and a fill factor (FF) of 5.6 mA cm⁻², 0.7 V and 0.78, respectively, with an overall power conversion efficiency (PCE) of 3.1%.