Photovoltaic Efficiency Enhancement by the Generation of an Embedded Silica-Like Passivation Layer along the P3HT/PCBM Interface Using an Asymmetric Block-Copolymer Additive

Advanced Materials

http://onlinelibrary.wiley.com/doi/10.1002/adma.201201994/abstract

A new approach to improve the power conversion efficiency of polymer bulk-heterojunction solar cells is demonstrated by generating a silica-like passivation layer embedded along the 3-dimensionally intertwined interfaces between the nanoscopic domains of P3HT and PCBM by addition of an aymmetric block copolymer containing a short organo-silica precursor. The additional thin interfacial layer was shown to act perfectly as a blocking layer, effectively depressing the recombination of charge carriers, affording about a 50% enhancement of the power conversion effi ciency over the devices without the copolymer.