Combined effects of MoO3 interlayer and PC70BM on polymer photovoltaic device performance

The performance of bulk-heterojunction solar cells fabricated from a donor-acceptor structured polymer designed to exhibit the color green (PGREEN) as the electron-donor, along with [6,6]-phenyl-C71 butyric acid methyl ester (PC70BM) as the electron-acceptor, are demonstrated with power conversion efficiency (PCE) up to 3.2% under air mass 1.5G, 100 mW/cm(2). The effects of anode interface layers (PEDOT:PSS, MoO3) and different acceptors (PC60BM, bis-PC60BM, PC70BM) on the cell performance were investigated. We found that the combined effect of PC70BM and a MoO3 anode interlayer exhibits a 69% enhancement in PCE compared to cells with PEDOT: PSS and PC60BM. This enhancement in PCE is attributed to combined effects of improved charge transport and strong light absorption by PC70BM, and efficient hole extraction by the MoO3 interlayer. (c) 2010 Elsevier B.V. All rights reserved.