AMPHIPHILYC LOW BAND-GAP ROD-COIL BLOCK COPOLYMERS: A TOOL FOR WATER-PROCESSABLE ORGANIC SOLAR CELLS

We report on the synthesis and photovoltaic application of rod-coil block copolymers (BCPs), PCPDTBT-b-P4VP, constituted by a low band-gap copolymer, PCPDTBT as the rigid segment, and tailored segments of poly-4-vinylpyridine (P4VP) able to interact with acceptor materials (fullerene derivatives, semiconducting NCs). Taking advantage of the hydrophilic behavior of their flexible moiety, these amphiphilic rod-coil BCPs were used for preparing nanoparticles (NPs) in blend with PCBM, through miniemulsion method in aqueous medium without use of surfactant agents. The NP films obtained from aqueous solvents were fully morphologically and electrically characterized and then used for the preparation of efficient organic solar cells. In this way we were able to control the morphology at the nanoscale and lower chlorinated solvents waste, thus reducing the environmental payback of the energy obtained from OPVs paving the way for the industrial application.