Porphyrin based push-pull conjugates as donors for solution-processed bulk heterojunction solar cells: a case of metal-dependent power conversion efficiency

Solution-processed bulk-heterojunction organic solar cells have been achieved using unsymmetrical metalloporphyrin-PBI dyads as small molecular donors. Due to panchromatic absorption, a photon-to-current conversion efficiency of 6.18% was obtained for 3-Zn:PC71BM with a remarkable energy loss (E-loss) of 0.60 eV, which is in line with the best values recorded so far for porphyrin-based small-molecular donors.