Study of Diketo-Pyrrolo-Pyrrole Polymers for Photovoltaic Applications

Using density-functional theory with the hybrid functional B3LYP, we investigate the electronic properties of polymers with diketo-pyrrolo-pyrrole (DPP) unit. We note that some of the polymers studied have LUCO energy similar to the C70-PCBM, or even lower, making them promising candidates for electron transport in organic photovoltaic devices. The homopolymer of DPP is predicted to have a band gap around 1.2 eV and shows a good dispersion of the conduction band.