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/cm2. 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.