Polydiacetylene-nested porphyrin as a potential light harvesting component in bulk heterojunction solar cells†
Abstract
A meso-substituted zinc-porphyrin embedded in a polydiacetylene web was prepared and tested for its potential in bulk heterojunction solar cells (BHJ-SCs). Light assisted formation of the polyenynes from diacetylenes coupled to the meso-position of the porphyrin were observed after UV-radiation, as evidenced by double and triple bond Raman-bands at 1446 and 2080 cm−1, respectively, and via UV absorption enhancement at 530–600 nm. Using cyclic voltammetry, Highest Occupied Molecular Orbital (HOMO) and Lowest Unoccupied Molecular Orbital (LUMO) energy levels were determined to be in an appropriate range for the photoactive materials in BHJ-SCs. Indeed, photoluminescence quenching indicated energy and/or charge transfer when the target material was used as a donor in combination with phenyl-C61-butyric acid methyl ester as acceptor in a blend. A photovoltaic effect of the BHJ-SCs was observed.